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Castelluccio N, Spath K, Li D, De Coo IFM, Butterworth L, Wells D, Mertes H, Poulton J, Heindryckx B. Genetic and reproductive strategies to prevent mitochondrial diseases. Hum Reprod Update 2025:dmaf004. [PMID: 40085924 DOI: 10.1093/humupd/dmaf004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2024] [Revised: 01/28/2025] [Indexed: 03/16/2025] Open
Abstract
Mitochondrial DNA (mtDNA) diseases pose unique challenges for genetic counselling and require tailored approaches to address recurrence risks and reproductive options. The intricate dynamics of mtDNA segregation and heteroplasmy shift significantly impact the chances of having affected children. In addition to natural pregnancy, oocyte donation, and adoption, IVF-based approaches can reduce the risk of disease transmission. Prenatal diagnosis (PND) and preimplantation genetic testing (PGT) remain the standard methods for women carrying pathogenic mtDNA mutations; nevertheless, they are not suitable for every patient. Germline nuclear transfer (NT) has emerged as a novel therapeutic strategy, while mitochondrial gene editing has increasingly become a promising research area in the field. However, challenges and safety concerns associated with all these techniques remain, highlighting the need for long-term follow-up studies, an improved understanding of disease mechanisms, and personalized approaches to diagnosis and treatment. Given the inherent risks of adverse maternal and child outcomes, careful consideration of the balance between potential benefits and drawbacks is also warranted. This review will provide critical insights, identify knowledge gaps, and underscore the importance of advancing mitochondrial disease research in reproductive health.
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Affiliation(s)
- Noemi Castelluccio
- Ghent-Fertility And Stem cell Team (G-FaST), Department for Reproductive Medicine, Department of Human Structure and Repair, Ghent University Hospital, Ghent, Belgium
| | | | - Danyang Li
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | - Irenaeus F M De Coo
- Department of Translational Genomics, Mental Health and Neuroscience Research Institute, Maastricht University, Maastricht, The Netherlands
| | - Lyndsey Butterworth
- FutureNeuro Research Ireland Centre for Translational Brain Science, RCSI University of Medicine and Health Sciences, Dublin, Ireland
| | - Dagan Wells
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
- Juno Genetics UK, Oxford, UK
| | - Heidi Mertes
- Department of Philosophy and Moral Sciences and Department of Public Health and Primary Care, Ghent University, Ghent, Belgium
| | - Joanna Poulton
- Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford, UK
| | - Björn Heindryckx
- Ghent-Fertility And Stem cell Team (G-FaST), Department for Reproductive Medicine, Department of Human Structure and Repair, Ghent University Hospital, Ghent, Belgium
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2
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Phua QH, Ng SY, Soh BS. Mitochondria: A Potential Rejuvenation Tool against Aging. Aging Dis 2024; 15:503-516. [PMID: 37815912 PMCID: PMC10917551 DOI: 10.14336/ad.2023.0712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 07/12/2023] [Indexed: 10/12/2023] Open
Abstract
Aging is a complex physiological process encompassing both physical and cognitive decline over time. This intricate process is governed by a multitude of hallmarks and pathways, which collectively contribute to the emergence of numerous age-related diseases. In response to the remarkable increase in human life expectancy, there has been a substantial rise in research focusing on the development of anti-aging therapies and pharmacological interventions. Mitochondrial dysfunction, a critical factor in the aging process, significantly impacts overall cellular health. In this extensive review, we will explore the contemporary landscape of anti-aging strategies, placing particular emphasis on the promising potential of mitotherapy as a ground-breaking approach to counteract the aging process. Moreover, we will investigate the successful application of mitochondrial transplantation in both animal models and clinical trials, emphasizing its translational potential. Finally, we will discuss the inherent challenges and future possibilities of mitotherapy within the realm of aging research and intervention.
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Affiliation(s)
- Qian Hua Phua
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- Department of Biological Sciences, National University of Singapore, Singapore.
| | - Shi Yan Ng
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- National University of Singapore, Yong Loo Lin School of Medicine (Department of Physiology), Singapore.
- National Neuroscience Institute, Singapore.
| | - Boon-Seng Soh
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), Proteos, Singapore.
- Department of Biological Sciences, National University of Singapore, Singapore.
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3
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Wal P, Wal A, Vig H, Mahmood D, Khan MMU. Potential Applications of Mitochondrial Therapy with a Focus on Parkinson's Disease and Mitochondrial Transplantation. Adv Pharm Bull 2024; 14:147-160. [PMID: 38585467 PMCID: PMC10997929 DOI: 10.34172/apb.2024.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/28/2023] [Accepted: 10/08/2023] [Indexed: 04/09/2024] Open
Abstract
Purpose Both aging and neurodegenerative illnesses are thought to be influenced by mitochondrial malfunction and free radical formation. Deformities of the energy metabolism, mitochondrial genome polymorphisms, nuclear DNA genetic abnormalities associated with mitochondria, modifications of mitochondrial fusion or fission, variations in shape and size, variations in transit, modified mobility of mitochondria, transcription defects, and the emergence of misfolded proteins associated with mitochondria are all linked to Parkinson's disease. Methods This review is a condensed compilation of data from research that has been published between the years of 2014 and 2022, using search engines like Google Scholar, PubMed, and Scopus. Results Mitochondrial transplantation is a one-of-a-kind treatment for mitochondrial diseases and deficits in mitochondrial biogenesis. The replacement of malfunctioning mitochondria with transplanted viable mitochondria using innovative methodologies has shown promising outcomes as a cure for Parkinson's, involving tissue sparing coupled with enhanced energy generation and lower oxidative damage. Numerous mitochondria-targeted therapies, including mitochondrial gene therapy, redox therapy, and others, have been investigated for their effectiveness and potency. Conclusion The development of innovative therapeutics for mitochondria-directed treatments in Parkinson's disease may be aided by optimizing mitochondrial dynamics. Many neurological diseases have been studied in animal and cellular models, and it has been found that mitochondrial maintenance can slow the death of neuronal cells. It has been hypothesized that drug therapies for neurodegenerative diseases that focus on mitochondrial dysfunction will help to delay the onset of neuronal dysfunction.
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Affiliation(s)
- Pranay Wal
- Pharmacy Department, PSIT- Pranveer Singh Institute of Technology, (PHARMACY) Kanpur-Agra-Delhi National Highway (NH-2), Bhauti-Kanpur-209305
| | - Ankita Wal
- Pharmacy Department, PSIT- Pranveer Singh Institute of Technology, (PHARMACY) Kanpur-Agra-Delhi National Highway (NH-2), Bhauti-Kanpur-209305
| | - Himangi Vig
- Pharmacy Department, PSIT- Pranveer Singh Institute of Technology, (PHARMACY) Kanpur-Agra-Delhi National Highway (NH-2), Bhauti-Kanpur-209305
| | - Danish Mahmood
- Department of Pharmacology and Toxicology, Unaizah College of Pharmacy, Unaizah 51911, Saudi Arabia
| | - Mohd Masih Uzzaman Khan
- Department of Pharmaceutical Chemistry and Pharmacognosy, Unaizah College of Pharmacy, Unaizah 51911, Saudi Arabia
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Clemente-Suárez VJ, Martín-Rodríguez A, Yáñez-Sepúlveda R, Tornero-Aguilera JF. Mitochondrial Transfer as a Novel Therapeutic Approach in Disease Diagnosis and Treatment. Int J Mol Sci 2023; 24:ijms24108848. [PMID: 37240194 DOI: 10.3390/ijms24108848] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 05/12/2023] [Accepted: 05/14/2023] [Indexed: 05/28/2023] Open
Abstract
Mitochondrial dysfunction is a hallmark of numerous diseases, including neurodegenerative disorders, metabolic disorders, and cancer. Mitochondrial transfer, the transfer of mitochondria from one cell to another, has recently emerged as a potential therapeutic approach for restoring mitochondrial function in diseased cells. In this review, we summarize the current understanding of mitochondrial transfer, including its mechanisms, potential therapeutic applications, and impact on cell death pathways. We also discuss the future directions and challenges in the field of mitochondrial transfer as a novel therapeutic approach in disease diagnosis and treatment.
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Affiliation(s)
| | | | - Rodrigo Yáñez-Sepúlveda
- Faculty of Education and Social Sciences, Universidad Andres Bello, Viña del Mar 2520000, Chile
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5
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Tolle I, Tiranti V, Prigione A. Modeling mitochondrial DNA diseases: from base editing to pluripotent stem-cell-derived organoids. EMBO Rep 2023; 24:e55678. [PMID: 36876467 PMCID: PMC10074100 DOI: 10.15252/embr.202255678] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 01/12/2023] [Accepted: 02/15/2023] [Indexed: 03/07/2023] Open
Abstract
Mitochondrial DNA (mtDNA) diseases are multi-systemic disorders caused by mutations affecting a fraction or the entirety of mtDNA copies. Currently, there are no approved therapies for the majority of mtDNA diseases. Challenges associated with engineering mtDNA have in fact hindered the study of mtDNA defects. Despite these difficulties, it has been possible to develop valuable cellular and animal models of mtDNA diseases. Here, we describe recent advances in base editing of mtDNA and the generation of three-dimensional organoids from patient-derived human-induced pluripotent stem cells (iPSCs). Together with already available modeling tools, the combination of these novel technologies could allow determining the impact of specific mtDNA mutations in distinct human cell types and might help uncover how mtDNA mutation load segregates during tissue organization. iPSC-derived organoids could also represent a platform for the identification of treatment strategies and for probing the in vitro effectiveness of mtDNA gene therapies. These studies have the potential to increase our mechanistic understanding of mtDNA diseases and may open the way to highly needed and personalized therapeutic interventions.
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Affiliation(s)
- Isabella Tolle
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Valeria Tiranti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Alessandro Prigione
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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6
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D'Amato M, Morra F, Di Meo I, Tiranti V. Mitochondrial Transplantation in Mitochondrial Medicine: Current Challenges and Future Perspectives. Int J Mol Sci 2023; 24:1969. [PMID: 36768312 PMCID: PMC9916997 DOI: 10.3390/ijms24031969] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
Mitochondrial diseases (MDs) are inherited genetic conditions characterized by pathogenic mutations in nuclear DNA (nDNA) or mitochondrial DNA (mtDNA). Current therapies are still far from being fully effective and from covering the broad spectrum of mutations in mtDNA. For example, unlike heteroplasmic conditions, MDs caused by homoplasmic mtDNA mutations do not yet benefit from advances in molecular approaches. An attractive method of providing dysfunctional cells and/or tissues with healthy mitochondria is mitochondrial transplantation. In this review, we discuss what is known about intercellular transfer of mitochondria and the methods used to transfer mitochondria both in vitro and in vivo, and we provide an outlook on future therapeutic applications. Overall, the transfer of healthy mitochondria containing wild-type mtDNA copies could induce a heteroplasmic shift even when homoplasmic mtDNA variants are present, with the aim of attenuating or preventing the progression of pathological clinical phenotypes. In summary, mitochondrial transplantation is a challenging but potentially ground-breaking option for the treatment of various mitochondrial pathologies, although several questions remain to be addressed before its application in mitochondrial medicine.
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Affiliation(s)
- Marco D'Amato
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Francesca Morra
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Ivano Di Meo
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Valeria Tiranti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
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7
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Kyrgiafini MA, Giannoulis T, Moutou KA, Mamuris Z. Investigating the Impact of a Curse: Diseases, Population Isolation, Evolution and the Mother's Curse. Genes (Basel) 2022; 13:2151. [PMID: 36421825 PMCID: PMC9690142 DOI: 10.3390/genes13112151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 09/08/2024] Open
Abstract
The mitochondrion was characterized for years as the energy factory of the cell, but now its role in many more cellular processes is recognized. The mitochondrion and mitochondrial DNA (mtDNA) also possess a set of distinct properties, including maternal inheritance, that creates the Mother's Curse phenomenon. As mtDNA is inherited from females to all offspring, mutations that are harmful to males tend to accumulate more easily. The Mother's Curse is associated with various diseases, and has a significant effect on males, in many cases even affecting their reproductive ability. Sometimes, it even leads to reproductive isolation, as in crosses between different populations, the mitochondrial genome cannot cooperate effectively with the nuclear one resulting in a mito-nuclear incompatibility and reduce the fitness of the hybrids. This phenomenon is observed both in the laboratory and in natural populations, and have the potential to influence their evolution and speciation. Therefore, it turns out that the study of mitochondria is an exciting field that finds many applications, including pest control, and it can shed light on the molecular mechanism of several diseases, improving successful diagnosis and therapeutics. Finally, mito-nuclear co-adaptation, paternal leakage, and kin selection are some mechanisms that can mitigate the impact of the Mother's Curse.
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Affiliation(s)
- Maria-Anna Kyrgiafini
- Laboratory of Genetics, Comparative and Evolutionary Biology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500 Larissa, Greece
| | - Themistoklis Giannoulis
- Laboratory of Biology, Genetics and Bioinformatics, Department of Animal Sciences, University of Thessaly, Gaiopolis, 41336 Larissa, Greece
| | - Katerina A. Moutou
- Laboratory of Genetics, Comparative and Evolutionary Biology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500 Larissa, Greece
| | - Zissis Mamuris
- Laboratory of Genetics, Comparative and Evolutionary Biology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500 Larissa, Greece
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8
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Chen Y, Yang F, Chu Y, Yun Z, Yan Y, Jin J. Mitochondrial transplantation: opportunities and challenges in the treatment of obesity, diabetes, and nonalcoholic fatty liver disease. Lab Invest 2022; 20:483. [PMID: 36273156 PMCID: PMC9588235 DOI: 10.1186/s12967-022-03693-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 10/06/2022] [Indexed: 11/23/2022]
Abstract
Metabolic diseases, including obesity, diabetes, and nonalcoholic fatty liver disease (NAFLD), are rising in both incidence and prevalence and remain a major global health and socioeconomic burden in the twenty-first century. Despite an increasing understanding of these diseases, the lack of effective treatments remains an ongoing challenge. Mitochondria are key players in intracellular energy production, calcium homeostasis, signaling, and apoptosis. Emerging evidence shows that mitochondrial dysfunction participates in the pathogeneses of metabolic diseases. Exogenous supplementation with healthy mitochondria is emerging as a promising therapeutic approach to treating these diseases. This article reviews recent advances in the use of mitochondrial transplantation therapy (MRT) in such treatment.
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Affiliation(s)
- Yifei Chen
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,School of Medicine, Jiangsu University, ZhenjiangJiangsu Province, 212013, China
| | - Fuji Yang
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,School of Medicine, Jiangsu University, ZhenjiangJiangsu Province, 212013, China
| | - Ying Chu
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.,Central Laboratory, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China
| | - Zhihua Yun
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China
| | - Yongmin Yan
- Department of Laboratory Medicine, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China. .,Central Laboratory, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.
| | - Jianhua Jin
- Department of Oncology, Wujin Hospital Affiliated With Jiangsu University (The Wujin Clinical College of Xuzhou Medical University), Changzhou, 213017, Jiangsu Province, China.
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9
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Zhang TG, Miao CY. Mitochondrial transplantation as a promising therapy for mitochondrial diseases. Acta Pharm Sin B 2022; 13:1028-1035. [PMID: 36970208 PMCID: PMC10031255 DOI: 10.1016/j.apsb.2022.10.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/25/2022] [Accepted: 08/18/2022] [Indexed: 11/28/2022] Open
Abstract
Mitochondrial diseases are a group of inherited or acquired metabolic disorders caused by mitochondrial dysfunction which may affect almost all the organs in the body and present at any age. However, no satisfactory therapeutic strategies have been available for mitochondrial diseases so far. Mitochondrial transplantation is a burgeoning approach for treatment of mitochondrial diseases by recovery of dysfunctional mitochondria in defective cells using isolated functional mitochondria. Many models of mitochondrial transplantation in cells, animals, and patients have proved effective via various routes of mitochondrial delivery. This review presents different techniques used in mitochondrial isolation and delivery, mechanisms of mitochondrial internalization and consequences of mitochondrial transplantation, along with challenges for clinical application. Despite some unknowns and challenges, mitochondrial transplantation would provide an innovative approach for mitochondrial medicine.
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Affiliation(s)
| | - Chao-yu Miao
- Corresponding author. Tel: +86 21 81871271; fax: +86 21 65493951.
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10
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Ma H, Van Dyken C, Darby H, Mikhalchenko A, Marti-Gutierrez N, Koski A, Liang D, Li Y, Tippner-Hedges R, Kang E, Lee Y, Sidener H, Ramsey C, Hodge T, Amato P, Mitalipov S. Germline transmission of donor, maternal and paternal mtDNA in primates. Hum Reprod 2021; 36:493-505. [PMID: 33289786 DOI: 10.1093/humrep/deaa308] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/12/2020] [Indexed: 12/11/2022] Open
Abstract
STUDY QUESTION What are the long-term developmental, reproductive and genetic consequences of mitochondrial replacement therapy (MRT) in primates? SUMMARY ANSWER Longitudinal investigation of MRT rhesus macaques (Macaca mulatta) generated with donor mtDNA that is exceedingly distant from the original maternal counterpart suggest that their growth, general health and fertility is unremarkable and similar to controls. WHAT IS KNOWN ALREADY Mitochondrial gene mutations contribute to a diverse range of incurable human disorders. MRT via spindle transfer in oocytes was developed and proposed to prevent transmission of pathogenic mtDNA mutations from mothers to children. STUDY DESIGN, SIZE, DURATION The study provides longitudinal studies on general health, fertility as well as transmission and segregation of parental mtDNA haplotypes to various tissues and organs in five adult MRT rhesus macaques and their offspring. PARTICIPANTS/MATERIALS, SETTING, METHODS MRT was achieved by spindle transfer between metaphase II oocytes from genetically divergent rhesus macaque populations. After fertilization of oocytes with sperm, heteroplasmic zygotes contained an unequal mixture of three parental genomes, i.e. donor (≥97%), maternal (≤3%), and paternal (≤0.1%) mitochondrial (mt)DNA. MRT monkeys were grown to adulthood and their development and general health was regularly monitored. Reproductive fitness of male and female MRT macaques was evaluated by time-mated breeding and production of live offspring. The relative contribution of donor, maternal, and paternal mtDNA was measured by whole mitochondrial genome sequencing in all organs and tissues of MRT animals and their offspring. MAIN RESULTS AND THE ROLE OF CHANCE Both male and female MRT rhesus macaques containing unequal mixture of three parental genomes, i.e. donor (≥97%), maternal (≤3%), and paternal (≤0.1%) mtDNA reached healthy adulthood, were fertile and most animals stably maintained the initial ratio of parental mtDNA heteroplasmy and donor mtDNA was transmitted from females to offspring. However, in one monkey out of four analyzed, initially negligible maternal mtDNA heteroplasmy levels increased substantially up to 17% in selected internal tissues and organs. In addition, two monkeys showed paternal mtDNA contribution up to 33% in selected internal tissues and organs. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION Conclusions in this study were made on a relatively low number of MRT monkeys, and on only one F1 (first generation) female. In addition, monkey MRT involved two wildtype mtDNA haplotypes, but not disease-relevant variants. Clinical trials on children born after MRT will be required to fully determine safety and efficacy of MRT for humans. WIDER IMPLICATIONS OF THE FINDINGS Our data show that MRT is compatible with normal postnatal development including overall health and reproductive fitness in nonhuman primates without any detected adverse effects. 'Mismatched' donor mtDNA in MRT animals even from the genetically distant mtDNA haplotypes did not cause secondary mitochondrial dysfunction. However, carry-over maternal or paternal mtDNA contributions increased substantially in selected internal tissues / organs of some MRT animals implying the possibility of mtDNA mutation recurrence. STUDY FUNDING/COMPETING INTEREST(S) This work has been funded by the grants from the Burroughs Wellcome Fund, the National Institutes of Health (RO1AG062459 and P51 OD011092), National Research Foundation of Korea (2018R1D1A1B07043216) and Oregon Health & Science University institutional funds. The authors declare no competing interests.
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Affiliation(s)
- Hong Ma
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.,Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Crystal Van Dyken
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.,Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Hayley Darby
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.,Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Aleksei Mikhalchenko
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Nuria Marti-Gutierrez
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Amy Koski
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Dan Liang
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Ying Li
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Rebecca Tippner-Hedges
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA
| | - Eunju Kang
- Stem Cell Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yeonmi Lee
- Stem Cell Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Heather Sidener
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Cathy Ramsey
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Travis Hodge
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
| | - Paula Amato
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.,Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Oregon Health & Science University, Portland, OR, USA
| | - Shoukhrat Mitalipov
- Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.,Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA
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Bennett JP, Onyango IG. Energy, Entropy and Quantum Tunneling of Protons and Electrons in Brain Mitochondria: Relation to Mitochondrial Impairment in Aging-Related Human Brain Diseases and Therapeutic Measures. Biomedicines 2021; 9:225. [PMID: 33671585 PMCID: PMC7927033 DOI: 10.3390/biomedicines9020225] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/18/2021] [Accepted: 02/18/2021] [Indexed: 11/16/2022] Open
Abstract
Adult human brains consume a disproportionate amount of energy substrates (2-3% of body weight; 20-25% of total glucose and oxygen). Adenosine triphosphate (ATP) is a universal energy currency in brains and is produced by oxidative phosphorylation (OXPHOS) using ATP synthase, a nano-rotor powered by the proton gradient generated from proton-coupled electron transfer (PCET) in the multi-complex electron transport chain (ETC). ETC catalysis rates are reduced in brains from humans with neurodegenerative diseases (NDDs). Declines of ETC function in NDDs may result from combinations of nitrative stress (NS)-oxidative stress (OS) damage; mitochondrial and/or nuclear genomic mutations of ETC/OXPHOS genes; epigenetic modifications of ETC/OXPHOS genes; or defects in importation or assembly of ETC/OXPHOS proteins or complexes, respectively; or alterations in mitochondrial dynamics (fusion, fission, mitophagy). Substantial free energy is gained by direct O2-mediated oxidation of NADH. Traditional ETC mechanisms require separation between O2 and electrons flowing from NADH/FADH2 through the ETC. Quantum tunneling of electrons and much larger protons may facilitate this separation. Neuronal death may be viewed as a local increase in entropy requiring constant energy input to avoid. The ATP requirement of the brain may partially be used for avoidance of local entropy increase. Mitochondrial therapeutics seeks to correct deficiencies in ETC and OXPHOS.
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Affiliation(s)
| | - Isaac G. Onyango
- International Clinical Research Center, St. Anne’s University Hospital, CZ-65691 Brno, Czech Republic;
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12
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Sendra L, García-Mares A, Herrero MJ, Aliño SF. Mitochondrial DNA Replacement Techniques to Prevent Human Mitochondrial Diseases. Int J Mol Sci 2021; 22:E551. [PMID: 33430493 PMCID: PMC7827455 DOI: 10.3390/ijms22020551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/03/2021] [Accepted: 01/04/2021] [Indexed: 01/27/2023] Open
Abstract
Background: Mitochondrial DNA (mtDNA) diseases are a group of maternally inherited genetic disorders caused by a lack of energy production. Currently, mtDNA diseases have a poor prognosis and no known cure. The chance to have unaffected offspring with a genetic link is important for the affected families, and mitochondrial replacement techniques (MRTs) allow them to do so. MRTs consist of transferring the nuclear DNA from an oocyte with pathogenic mtDNA to an enucleated donor oocyte without pathogenic mtDNA. This paper aims to determine the efficacy, associated risks, and main ethical and legal issues related to MRTs. Methods: A bibliographic review was performed on the MEDLINE and Web of Science databases, along with searches for related clinical trials and news. Results: A total of 48 publications were included for review. Five MRT procedures were identified and their efficacy was compared. Three main risks associated with MRTs were discussed, and the ethical views and legal position of MRTs were reviewed. Conclusions: MRTs are an effective approach to minimizing the risk of transmitting mtDNA diseases, but they do not remove it entirely. Global legal regulation of MRTs is required.
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Affiliation(s)
- Luis Sendra
- Unidad de Farmacogenética, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain; (L.S.); (S.F.A.)
- Departamento de Farmacología, Facultad de Medicina, Universidad de Valencia, 46010 Valencia, Spain;
| | - Alfredo García-Mares
- Departamento de Farmacología, Facultad de Medicina, Universidad de Valencia, 46010 Valencia, Spain;
| | - María José Herrero
- Unidad de Farmacogenética, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain; (L.S.); (S.F.A.)
- Departamento de Farmacología, Facultad de Medicina, Universidad de Valencia, 46010 Valencia, Spain;
| | - Salvador F. Aliño
- Unidad de Farmacogenética, Instituto de Investigación Sanitaria La Fe, 46026 Valencia, Spain; (L.S.); (S.F.A.)
- Departamento de Farmacología, Facultad de Medicina, Universidad de Valencia, 46010 Valencia, Spain;
- Unidad de Farmacología Clínica, Área del Medicamento, Hospital Universitario y Politécnico La Fe, 46026 Valencia, Spain
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13
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F C Lopes A. Mitochondrial metabolism and DNA methylation: a review of the interaction between two genomes. Clin Epigenetics 2020; 12:182. [PMID: 33228792 PMCID: PMC7684747 DOI: 10.1186/s13148-020-00976-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/10/2020] [Indexed: 02/06/2023] Open
Abstract
Mitochondria are controlled by the coordination of two genomes: the mitochondrial and the nuclear DNA. As such, variations in nuclear gene expression as a consequence of mutations and epigenetic modifications can affect mitochondrial functionality. Conversely, the opposite could also be true. However, the relationship between mitochondrial dysfunction and epigenetics, such as nuclear DNA methylation, remains largely unexplored. Mitochondria function as central metabolic hubs controlling some of the main substrates involved in nuclear DNA methylation, via the one carbon metabolism, the tricarboxylic acid cycle and the methionine pathway. Here, we review key findings and highlight new areas of focus, with the ultimate goal of getting one step closer to understanding the genomic effects of mitochondrial dysfunction on nuclear epigenetic landscapes.
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Affiliation(s)
- Amanda F C Lopes
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK.
- Medical Research Council - Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK.
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14
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Sharma H, Singh D, Mahant A, Sohal SK, Kesavan AK, Samiksha. Development of mitochondrial replacement therapy: A review. Heliyon 2020; 6:e04643. [PMID: 32984570 PMCID: PMC7492815 DOI: 10.1016/j.heliyon.2020.e04643] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/10/2020] [Accepted: 08/03/2020] [Indexed: 12/19/2022] Open
Abstract
Mitochondrial replacement therapy (MRT) is a new form of reproductive invitro fertilization (IVF) which works on the principle of replacing a women's abnormal mitochondrial DNA (mt-DNA) with the donor's healthy one. MRT include different techniques like spindles transfer (ST), pronuclear transfer (PNT) or polar body transfer (PBT). Transmission of defective mitochondrial DNA to the next generation can also be prevented by using these approaches. The development of healthy baby free from genetic disorders and to terminate the lethal mitochondrial disorders are the chief motive of this technique. In aged individuals, through in vitro fertilization, MRT provides the substitution of defective cytoplasm with cured one to enhance the expectation of pregnancy rates. However, moral, social, and cultural objections have restricted its exploration. Therefore, this review summarizes the various methods involved in MRT, its global status, its exaggerated censure over the years which depicts a strong emphasis for social acceptance and clinical application in the world of medical science.
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Affiliation(s)
- Hitika Sharma
- Department of Zoology, Khalsa College Amritsar, Punjab, 143005, India
| | - Drishtant Singh
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, 143005, India
| | | | - Satwinder Kaur Sohal
- Department of Zoology, Guru Nanak Dev University Amritsar, Punjab, 143005, India
| | - Anup Kumar Kesavan
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, 143005, India
| | - Samiksha
- Department of Zoology, Guru Nanak Dev University Amritsar, Punjab, 143005, India
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15
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Wei W, Chinnery PF. Inheritance of mitochondrial DNA in humans: implications for rare and common diseases. J Intern Med 2020; 287:634-644. [PMID: 32187761 PMCID: PMC8641369 DOI: 10.1111/joim.13047] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 11/01/2019] [Accepted: 12/10/2019] [Indexed: 12/27/2022]
Abstract
The first draft human mitochondrial DNA (mtDNA) sequence was published in 1981, paving the way for two decades of discovery linking mtDNA variation with human disease. Severe pathogenic mutations cause sporadic and inherited rare disorders that often involve the nervous system. However, some mutations cause mild organ-specific phenotypes that have a reduced clinical penetrance, and polymorphic variation of mtDNA is associated with an altered risk of developing several late-onset common human diseases including Parkinson's disease. mtDNA mutations also accumulate during human life and are enriched in affected organs in a number of age-related diseases. Thus, mtDNA contributes to a wide range of human pathologies. For many decades, it has generally been accepted that mtDNA is inherited exclusively down the maternal line in humans. Although recent evidence has challenged this dogma, whole-genome sequencing has identified nuclear-encoded mitochondrial sequences (NUMTs) that can give the false impression of paternally inherited mtDNA. This provides a more likely explanation for recent reports of 'bi-parental inheritance', where the paternal alleles are actually transmitted through the nuclear genome. The presence of both mutated and wild-type variant alleles within the same individual (heteroplasmy) and rapid shifts in allele frequency can lead to offspring with variable severity of disease. In addition, there is emerging evidence that selection can act for and against specific mtDNA variants within the developing germ line, and possibly within developing tissues. Thus, understanding how mtDNA is inherited has far-reaching implications across medicine. There is emerging evidence that this highly dynamic system is amenable to therapeutic manipulation, raising the possibility that we can harness new understanding to prevent and treat rare and common human diseases where mtDNA mutations play a key role.
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Affiliation(s)
- W Wei
- From the, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - P F Chinnery
- From the, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK.,Medical Research Council Mitochondrial Biology Unit, School of Clinical Medicine, University of Cambridge, Cambridge, UK
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16
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Hill GE, Havird JC, Sloan DB, Burton RS, Greening C, Dowling DK. Assessing the fitness consequences of mitonuclear interactions in natural populations. Biol Rev Camb Philos Soc 2019; 94:1089-1104. [PMID: 30588726 PMCID: PMC6613652 DOI: 10.1111/brv.12493] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 12/22/2022]
Abstract
Metazoans exist only with a continuous and rich supply of chemical energy from oxidative phosphorylation in mitochondria. The oxidative phosphorylation machinery that mediates energy conservation is encoded by both mitochondrial and nuclear genes, and hence the products of these two genomes must interact closely to achieve coordinated function of core respiratory processes. It follows that selection for efficient respiration will lead to selection for compatible combinations of mitochondrial and nuclear genotypes, and this should facilitate coadaptation between mitochondrial and nuclear genomes (mitonuclear coadaptation). Herein, we outline the modes by which mitochondrial and nuclear genomes may coevolve within natural populations, and we discuss the implications of mitonuclear coadaptation for diverse fields of study in the biological sciences. We identify five themes in the study of mitonuclear interactions that provide a roadmap for both ecological and biomedical studies seeking to measure the contribution of intergenomic coadaptation to the evolution of natural populations. We also explore the wider implications of the fitness consequences of mitonuclear interactions, focusing on central debates within the fields of ecology and biomedicine.
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Affiliation(s)
- Geoffrey E. Hill
- Department of Biological Sciences, Auburn University, United States of America
| | - Justin C. Havird
- Department of Biology, Colorado State University, United States of America
| | - Daniel B. Sloan
- Department of Biology, Colorado State University, United States of America
| | - Ronald S. Burton
- Scripps Institution of Oceanography, University of California, San Diego, United States of America
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
| | - Damian K. Dowling
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia
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17
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Palacios-González C, Cavaliere G. 'Yes' to mitochondrial replacement techniques and lesbian motherhood: a reply to Françoise Baylis. JOURNAL OF MEDICAL ETHICS 2019; 45:280-281. [PMID: 30463932 DOI: 10.1136/medethics-2018-105060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/05/2018] [Accepted: 10/27/2018] [Indexed: 06/09/2023]
Abstract
In a recent paper - Lesbian motherhood and mitochondrial replacement techniques: reproductive freedom and genetic kinship - we argued that lesbian couples who wish to have children who are genetically related to both of them should be allowed access to mitochondrial replacement techniques (MRTs). Françoise Baylis wrote a reply to our paper -'No' to lesbian motherhood using human nuclear genome transfer- where she challenges our arguments on the use of MRTs by lesbian couples, and on MRTs more generally. In this reply we respond to her claims and further clarify our position.
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Affiliation(s)
| | - Giulia Cavaliere
- Department of Global Health and Social Medicine, King's College London, London, UK
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18
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Dobler R, Dowling DK, Morrow EH, Reinhardt K. A systematic review and meta-analysis reveals pervasive effects of germline mitochondrial replacement on components of health. Hum Reprod Update 2019; 24:519-534. [PMID: 29757366 DOI: 10.1093/humupd/dmy018] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 05/03/2018] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Mitochondrial replacement, a form of nuclear transfer, has been proposed as a germline therapy to prevent the transmission of mitochondrial diseases. Mitochondrial replacement therapy has been licensed for clinical application in the UK, and already carried out in other countries, but little is known about negative or unintended effects on the health of offspring born using this technique. OBJECTIVE AND RATIONALE Studies in invertebrate models have used techniques that achieve mitochondrial replacement to create offspring with novel combinations of mitochondrial and nuclear genotype. These have demonstrated that the creation of novel mitochondrial-nuclear interactions can lead to alterations in offspring characteristics, such as development rates, fertility and longevity. However, it is currently unclear whether such interactions could similarly affect the outcomes of vertebrate biomedical studies, which have sought to assess the efficacy of the replacement therapy. SEARCH METHODS This systematic review addresses whether the effects of mitochondrial replacement on offspring characteristics differ in magnitude between biological (conducted on invertebrate models, with an ecological or evolutionary focus) and biomedical studies (conducted on vertebrate models, with a clinical focus). Studies were selected based on a key-word search in 'Web of Science', complemented by backward searches of reviews on the topic of mitochondrial-nuclear (mito-nuclear) interactions. In total, 43 of the resulting 116 publications identified in the search contained reliable data to estimate effect sizes of mitochondrial replacement. We found no evidence of publication bias when examining effect-size estimates across sample sizes. OUTCOMES Mitochondrial replacement consistently altered the phenotype, with significant effects at several levels of organismal performance and health, including gene expression, anatomy, metabolism and life-history. Biomedical and biological studies, while differing in the methods used to achieve mitochondrial replacement, showed only marginally significant differences in effect-size estimates (-0.233 [CI: -0.495 to -0.011]), with larger effect-size estimates in biomedical studies (0.697 [CI: 0.450-0.956]) than biological studies (0.462 [CI: 0.287-0.688]). Humans showed stronger effects than other species. Effects of mitochondrial replacement were also stronger in species with a higher basal metabolic rate. Based on our results, we conducted the first formal risk analysis of mitochondrial replacement, and conservatively estimate negative effects in at least one in every 130 resulting offspring born to the therapy. WIDER IMPLICATIONS Our findings suggest that mitochondrial replacement may routinely affect offspring characteristics across a wide array of animal species, and that such effects are likely to extend to humans. Studies in invertebrate models have confirmed mito-nuclear interactions as the underpinning cause of organismal effects following mitochondrial replacement. This therefore suggests that mito-nuclear interactions are also likely to be contributing to effects seen in biomedical studies, on vertebrate models, whose effect sizes exceeded those of biological studies. Our results advocate the use of safeguards that could offset any negative effects (defining any unintended effect as being negative) mediated by mito-nuclear interactions following mitochondrial replacement in humans, such as mitochondrial genetic matching between donor and recipient. Our results also suggest that further research into the molecular nature of mito-nuclear interactions would be beneficial in refining the clinical application of mitochondrial replacement, and in establishing what degree of variation between donor and patient mitochondrial DNA haplotypes is acceptable to ensure 'haplotype matching'.
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Affiliation(s)
- Ralph Dobler
- Applied Zoology, Technische Universität Dresden, Zellescher Weg 20b, Dresden, Germany
| | - Damian K Dowling
- School of Biological Sciences, Monash University, Clayton, Vic., Australia
| | - Edward H Morrow
- Evolution, Behaviour and Environment Group, School of Life Sciences, University of Sussex, Brighton, UK
| | - Klaus Reinhardt
- Applied Zoology, Technische Universität Dresden, Zellescher Weg 20b, Dresden, Germany
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19
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Waltz F, Nguyen TT, Arrivé M, Bochler A, Chicher J, Hammann P, Kuhn L, Quadrado M, Mireau H, Hashem Y, Giegé P. Small is big in Arabidopsis mitochondrial ribosome. NATURE PLANTS 2019; 5:106-117. [PMID: 30626926 DOI: 10.1038/s41477-018-0339-y] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 11/27/2018] [Indexed: 05/24/2023]
Abstract
Mitochondria are responsible for energy production through aerobic respiration, and represent the powerhouse of eukaryotic cells. Their metabolism and gene expression processes combine bacterial-like features and traits that evolved in eukaryotes. Among mitochondrial gene expression processes, translation remains the most elusive. In plants, while numerous pentatricopeptide repeat (PPR) proteins are involved in all steps of gene expression, their function in mitochondrial translation remains unclear. Here we present the biochemical characterization of Arabidopsis mitochondrial ribosomes and identify their protein subunit composition. Complementary biochemical approaches identified 19 plant-specific mitoribosome proteins, of which ten are PPR proteins. The knockout mutations of ribosomal PPR (rPPR) genes result in distinct macroscopic phenotypes, including lethality and severe growth delay. The molecular analysis of rppr1 mutants using ribosome profiling, as well as the analysis of mitochondrial protein levels, demonstrate rPPR1 to be a generic translation factor that is a novel function for PPR proteins. Finally, single-particle cryo-electron microscopy (cryo-EM) reveals the unique structural architecture of Arabidopsis mitoribosomes, characterized by a very large small ribosomal subunit, larger than the large subunit, bearing an additional RNA domain grafted onto the head. Overall, our results show that Arabidopsis mitoribosomes are substantially divergent from bacterial and other eukaryote mitoribosomes, in terms of both structure and protein content.
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Affiliation(s)
- Florent Waltz
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Tan-Trung Nguyen
- Institut Jean-Pierre Bourgin INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles, France
| | - Mathilde Arrivé
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Anthony Bochler
- Institut Européen de Chimie et Biologie U1212 Inserm, Université de Bordeaux, Pessac, France
| | - Johana Chicher
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Philippe Hammann
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Lauriane Kuhn
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Martine Quadrado
- Institut Jean-Pierre Bourgin INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles, France
| | - Hakim Mireau
- Institut Jean-Pierre Bourgin INRA, AgroParisTech, CNRS, Université Paris-Saclay, Versailles, France.
| | - Yaser Hashem
- Institut Européen de Chimie et Biologie U1212 Inserm, Université de Bordeaux, Pessac, France.
| | - Philippe Giegé
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
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Sloan DB, Warren JM, Williams AM, Wu Z, Abdel-Ghany SE, Chicco AJ, Havird JC. Cytonuclear integration and co-evolution. Nat Rev Genet 2018; 19:635-648. [PMID: 30018367 PMCID: PMC6469396 DOI: 10.1038/s41576-018-0035-9] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The partitioning of genetic material between the nucleus and cytoplasmic (mitochondrial and plastid) genomes within eukaryotic cells necessitates coordinated integration between these genomic compartments, with important evolutionary and biomedical implications. Classic questions persist about the pervasive reduction of cytoplasmic genomes via a combination of gene loss, transfer and functional replacement - and yet why they are almost always retained in some minimal form. One striking consequence of cytonuclear integration is the existence of 'chimeric' enzyme complexes composed of subunits encoded in two different genomes. Advances in structural biology and comparative genomics are yielding important insights into the evolution of such complexes, including correlated sequence changes and recruitment of novel subunits. Thus, chimeric cytonuclear complexes provide a powerful window into the mechanisms of molecular co-evolution.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, USA.
| | - Jessica M Warren
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Alissa M Williams
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Zhiqiang Wu
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | | | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Justin C Havird
- Department of Biology, Colorado State University, Fort Collins, CO, USA
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21
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Kim US, Jurkute N, Yu-Wai-Man P. Leber Hereditary Optic Neuropathy-Light at the End of the Tunnel? Asia Pac J Ophthalmol (Phila) 2018; 7:242-245. [PMID: 30008192 DOI: 10.22608/apo.2018293] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Leber hereditary optic neuropathy (LHON) is an important cause of mitochondrial blindness. The majority of patients harbor one of three mitochondrial DNA (mtDNA) point mutations, m.3460G>A, m.11778G>A, and m.14484T>C, which all affect complex I subunits of the mitochondrial respiratory chain. The loss of retinal ganglion cells in LHON is thought to arise from a combination of impaired mitochondrial oxidative phosphorylation resulting in decreased adenosine triphosphate (ATP) production and increased levels of reactive oxygen species. Treatment options for LHON remain limited, but major advances in mitochondrial neuroprotection, gene therapy, and the prevention of transmission of pathogenic mtDNA mutations will hopefully translate into tangible benefits for patients affected by this condition and their families.
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Affiliation(s)
- Ungsoo Samuel Kim
- Kim's Eye Hospital, Seoul, South Korea
- Department of Ophthalmology, Konyang University College of Medicine, Daejeon, South Korea
| | - Neringa Jurkute
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom
| | - Patrick Yu-Wai-Man
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom
- Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
- Cambridge Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
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22
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Kristensen SG, Humaidan P, Coetzee K. Mitochondria and reproduction: possibilities for testing and treatment. Panminerva Med 2018; 61:82-96. [PMID: 29962188 DOI: 10.23736/s0031-0808.18.03510-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mitochondria, known as the energy factories in all cells, are key regulators of multiple vital cellular processes and affect all aspects of mammalian reproduction, being essential for oocyte maturation, fertilization and embryonic development. Mitochondrial dysfunction is consequently implicated in disease as well as age-related infertility. Since mitochondria are inherited exclusively from the mother, the female gamete is central to reproductive outcome and therapeutic interventions, such as mitochondrial replacement therapy (MRT), and development of new diagnostic tools. The primary purpose of MRT is to improve oocyte quality, embryogenesis and fetal development by correcting the imbalance between mutant and wild-type mitochondrial DNA (mtDNA) in the oocyte or zygote, either by replacing mutant mtDNA or supplementing with wild-type counterparts from heterologous or autologous sources. However, the efficacy and safety of these new technologies have not yet been tested in clinical trials, and various concerns exist. Nonetheless, the perspectives for such procedures are intriguing and include two distinct patient populations that could potentially benefit from the clinical implementation of MRT; 1) patients with mtDNA-disease transmission risk; 2) patients undergoing IVF with recurrent poor embryo outcomes due to advanced maternal age. In this review, we outline the intrinsic roles of mitochondria during oogenesis and early embryogenesis in relation to disease and infertility, and discuss the progress in MRT with the developments in reproductive technologies and the related concerns. In addition, we assess the use of mtDNA as a potential biomarker for embryo viability in assisted reproduction.
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Affiliation(s)
- Stine G Kristensen
- Laboratory of Reproductive Biology, University Hospital of Copenhagen, Copenhagen, Denmark -
| | - Peter Humaidan
- The Fertility Clinic, Skive Regional Hospital and Faculty of Health, Aarhus University, Aarhus, Denmark
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23
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Sharbrough J, Havird JC, Noe GR, Warren JM, Sloan DB. The Mitonuclear Dimension of Neanderthal and Denisovan Ancestry in Modern Human Genomes. Genome Biol Evol 2018; 9:1567-1581. [PMID: 28854627 PMCID: PMC5509035 DOI: 10.1093/gbe/evx114] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2017] [Indexed: 12/15/2022] Open
Abstract
Some human populations interbred with Neanderthals and Denisovans, resulting in substantial contributions to modern-human genomes. Therefore, it is now possible to use genomic data to investigate mechanisms that shaped historical gene flow between humans and our closest hominin relatives. More generally, in eukaryotes, mitonuclear interactions have been argued to play a disproportionate role in generating reproductive isolation. There is no evidence of mtDNA introgression into modern human populations, which means that all introgressed nuclear alleles from archaic hominins must function on a modern-human mitochondrial background. Therefore, mitonuclear interactions are also potentially relevant to hominin evolution. We performed a detailed accounting of mtDNA divergence among hominin lineages and used population-genomic data to test the hypothesis that mitonuclear incompatibilities have preferentially restricted the introgression of nuclear genes with mitochondrial functions. We found a small but significant underrepresentation of introgressed Neanderthal alleles at such nuclear loci. Structural analyses of mitochondrial enzyme complexes revealed that these effects are unlikely to be mediated by physically interacting sites in mitochondrial and nuclear gene products. We did not detect any underrepresentation of introgressed Denisovan alleles at mitochondrial-targeted loci, but this may reflect reduced power because locus-specific estimates of Denisovan introgression are more conservative. Overall, we conclude that genes involved in mitochondrial function may have been subject to distinct selection pressures during the history of introgression from archaic hominins but that mitonuclear incompatibilities have had, at most, a small role in shaping genome-wide introgression patterns, perhaps because of limited functional divergence in mtDNA and interacting nuclear genes.
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Affiliation(s)
- Joel Sharbrough
- Department of Biology, Colorado State University, Fort Collins, CO
| | - Justin C Havird
- Department of Biology, Colorado State University, Fort Collins, CO
| | - Gregory R Noe
- Department of Biology, Colorado State University, Fort Collins, CO
| | - Jessica M Warren
- Department of Biology, Colorado State University, Fort Collins, CO
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO
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24
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Poulton J, Finsterer J, Yu-Wai-Man P. Genetic Counselling for Maternally Inherited Mitochondrial Disorders. Mol Diagn Ther 2018; 21:419-429. [PMID: 28536827 DOI: 10.1007/s40291-017-0279-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The aim of this review was to provide an evidence-based approach to frequently asked questions relating to the risk of transmitting a maternally inherited mitochondrial disorder (MID). We do not address disorders linked with disturbed mitochondrial DNA (mtDNA) maintenance, causing mtDNA depletion or multiple mtDNA deletions, as these are autosomally inherited. The review addresses questions regarding prognosis, recurrence risks and the strategies available to prevent disease transmission. The clinical and genetic complexity of maternally inherited MIDs represent a major challenge for patients, their relatives and health professionals. Since many of the genetic and pathophysiological aspects of MIDs remain unknown, counselling of affected patients and at-risk family members remains difficult. MtDNA mutations are maternally transmitted or, more rarely, they are sporadic, occurring de novo (~25%). Females carrying homoplasmic mtDNA mutations will transmit the mutant species to all of their offspring, who may or may not exhibit a similar phenotype depending on modifying, secondary factors. Females carrying heteroplasmic mtDNA mutations will transmit a variable amount of mutant mtDNA to their offspring, which can result in considerable phenotypic heterogeneity among siblings. The majority of mtDNA rearrangements, such as single large-scale deletions, are sporadic, but there is a small risk of recurrence (~4%) among the offspring of affected women. The range and suitability of reproductive choices for prospective mothers is a complex area of mitochondrial medicine that needs to be managed by experienced healthcare professionals as part of a multidisciplinary team. Genetic counselling is facilitated by the identification of the underlying causative genetic defect. To provide more precise genetic counselling, further research is needed to clarify the secondary factors that account for the variable penetrance and the often marked differential expressivity of pathogenic mtDNA mutations both within and between families.
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Affiliation(s)
- Joanna Poulton
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Oxford, UK
| | - Josef Finsterer
- Krankenanstalt Rudolfstiftung, Postfach 20, 1180, Vienna, Austria.
| | - Patrick Yu-Wai-Man
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.,Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK.,NIHR Biomedical Research Centre, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK.,Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
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25
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Adashi EY, Cohen IG. Preventing Mitochondrial Diseases: Embryo-Sparing Donor-Independent Options. Trends Mol Med 2018; 24:449-457. [PMID: 29605176 DOI: 10.1016/j.molmed.2018.03.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 03/04/2018] [Accepted: 03/05/2018] [Indexed: 12/26/2022]
Abstract
Mutant mitochondrial DNA gives rise to a broad range of incurable inborn maladies. Prevention may now be possible by replacing the mutation-carrying mitochondria of zygotes or oocytes at risk with donated unaffected counterparts. However, mitochondrial replacement therapy is being held back by theological, ethical, and safety concerns over the loss of human zygotes and the involvement of a donor. These concerns make it plain that the identification, validation, and regulatory adjudication of novel embryo-sparing donor-independent technologies remains a pressing imperative. This Opinion highlights three emerging embryo-sparing donor-independent options that stand to markedly allay theological, ethical, and safety concerns raised by mitochondrial replacement therapy.
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Affiliation(s)
- Eli Y Adashi
- The Warren Alpert Medical School, Brown University, Providence, RI 02905, USA.
| | - I Glenn Cohen
- Harvard Law School, Cambridge, MA 02138, USA; Petrie-Flom Center for Health Law Policy, Biotechnology, and Bioethics, Harvard University, 1563 Massachusetts Avenue, Cambridge, MA 02138, USA
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26
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Harnessing the Power of Genetic Engineering for Patients With Mitochondrial Eye Diseases. J Neuroophthalmol 2018; 37:56-64. [PMID: 28187082 DOI: 10.1097/wno.0000000000000476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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Craven L, Tang MX, Gorman GS, De Sutter P, Heindryckx B. Novel reproductive technologies to prevent mitochondrial disease. Hum Reprod Update 2018. [PMID: 28651360 DOI: 10.1093/humupd/dmx018] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The use of nuclear transfer (NT) has been proposed as a novel reproductive treatment to overcome the transmission of maternally-inherited mitochondrial DNA (mtDNA) mutations. Pathogenic mutations in mtDNA can cause a wide-spectrum of life-limiting disorders, collectively known as mtDNA disease, for which there are currently few effective treatments and no known cures. The many unique features of mtDNA make genetic counselling challenging for women harbouring pathogenic mtDNA mutations but reproductive options that involve medical intervention are available that will minimize the risk of mtDNA disease in their offspring. This includes PGD, which is currently offered as a clinical treatment but will not be suitable for all. The potential for NT to reduce transmission of mtDNA mutations has been demonstrated in both animal and human models, and has recently been clinically applied not only to prevent mtDNA disease but also for some infertility cases. In this review, we will interrogate the different NT techniques, including a discussion on the available safety and efficacy data of these technologies for mtDNA disease prevention. In addition, we appraise the evidence for the translational use of NT technologies in infertility. OBJECTIVE AND RATIONALE We propose to review the current scientific evidence regarding the clinical use of NT to prevent mitochondrial disease. SEARCH METHODS The scientific literature was investigated by searching PubMed database until Jan 2017. Relevant documents from Human Fertilisation and Embryology Authority as well as reports from both the scientific and popular media were also implemented. The above searches were based on the following key words: 'mitochondria', 'mitochondrial DNA'; 'mitochondrial DNA disease', 'fertility'; 'preimplantation genetic diagnosis', 'nuclear transfer', 'mitochondrial replacement' and 'mitochondrial donation'. OUTCOMES While NT techniques have been shown to effectively reduce the transmission of heteroplasmic mtDNA variants in animal models, and increasing evidence supports their use to prevent the transmission of human mtDNA disease, the need for robust, long-term evaluation is still warranted. Moreover, prenatal screening would still be strongly advocated in combination with the use of these IVF-based technologies. Scientific evidence to support the use of NT and other novel reproductive techniques for infertility is currently lacking. WIDER IMPLICATIONS It is mandatory that any new ART treatments are first adequately assessed in both animal and human models before the cautious implementation of these new therapeutic approaches is clinically undertaken. There is growing evidence to suggest that the translation of these innovative technologies into clinical practice should be cautiously adopted only in highly selected patients. Indeed, given the limited safety and efficacy data, close monitoring of any offspring remains paramount.
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Affiliation(s)
- Lyndsey Craven
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Mao-Xing Tang
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Gráinne S Gorman
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK
| | - Petra De Sutter
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Björn Heindryckx
- Ghent-Fertility and Stem Cell Team (G-FaST), Department for Reproductive Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
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28
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Burr SP, Pezet M, Chinnery PF. Mitochondrial DNA Heteroplasmy and Purifying Selection in the Mammalian Female Germ Line. Dev Growth Differ 2018; 60:21-32. [PMID: 29363102 PMCID: PMC11520955 DOI: 10.1111/dgd.12420] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 12/08/2017] [Indexed: 01/19/2023]
Abstract
Inherited mutations in the mitochondrial (mt)DNA are a major cause of human disease, with approximately 1 in 5000 people affected by one of the hundreds of identified pathogenic mtDNA point mutations or deletions. Due to the severe, and often untreatable, symptoms of many mitochondrial diseases, identifying how these mutations are inherited from one generation to the next has been an area of intense research in recent years. Despite large advances in our understanding of this complex process, many questions remain unanswered, with one of the most hotly debated being whether or not purifying selection acts against pathogenic mutations during germline development.
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Affiliation(s)
- Stephen P. Burr
- MRC Mitochondrial Biology UnitDepartment of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Mikael Pezet
- MRC Mitochondrial Biology UnitDepartment of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Patrick F. Chinnery
- MRC Mitochondrial Biology UnitDepartment of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
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29
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Lima A, Burgstaller J, Sanchez-Nieto JM, Rodríguez TA. The Mitochondria and the Regulation of Cell Fitness During Early Mammalian Development. Curr Top Dev Biol 2017; 128:339-363. [PMID: 29477168 DOI: 10.1016/bs.ctdb.2017.10.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
From fertilization until the onset of gastrulation the early mammalian embryo undergoes a dramatic series of changes that converts a single fertilized cell into a remarkably complex organism. Much attention has been given to the molecular changes occurring during this process, but here we will review what is known about the changes affecting the mitochondria and how they impact on the energy metabolism and apoptotic response of the embryo. We will also focus on understanding what quality control mechanisms ensure optimal mitochondrial activity in the embryo, and in this way provide an overview of the importance of the mitochondria in determining cell fitness during early mammalian development.
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Affiliation(s)
- Ana Lima
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom; Cell Stress Group, MRC London Institute of Medical Sciences (LMS), London, United Kingdom
| | - Jörg Burgstaller
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom; Biotechnology in Animal Production, Department for Agrobiotechnology, IFA Tulln, Tulln, Austria
| | - Juan M Sanchez-Nieto
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom
| | - Tristan A Rodríguez
- British Heart Foundation Centre for Research Excellence, National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, United Kingdom.
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30
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Haimes E, Taylor K. Sharpening the cutting edge: additional considerations for the UK debates on embryonic interventions for mitochondrial diseases. LIFE SCIENCES, SOCIETY AND POLICY 2017; 13:1. [PMID: 28092013 PMCID: PMC5236032 DOI: 10.1186/s40504-016-0046-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 12/22/2016] [Indexed: 06/06/2023]
Abstract
In October 2015 the UK enacted legislation to permit the clinical use of two cutting edge germline-altering, IVF-based embryonic techniques: pronuclear transfer and maternal spindle transfer (PNT and MST). The aim is to use these techniques to prevent the maternal transmission of serious mitochondrial diseases. Major claims have been made about the quality of the debates that preceded this legislation and the significance of those debates for UK decision-making on other biotechnologies, as well as for other countries considering similar legislation. In this article we conduct a systematic analysis of those UK debates and suggest that claims about their quality are over-stated. We identify, and analyse in detail, ten areas where greater clarity, depth and nuance would have produced sharper understandings of the contributions, limitations and wider social impacts of these mitochondrial interventions. We explore the implications of these additional considerations for (i) the protection of all parties involved, should the techniques transfer to clinical applications; (ii) the legitimacy of focussing on short-term gains for individuals over public health considerations, and (iii) the maintenance and improvement of public trust in medical biotechnologies. We conclude that a more measured evaluation of the content and quality of the UK debates is important and timely: such a critique provides a clearer understanding of the possible, but specific, contributions of these interventions, both in the UK and elsewhere; also, these additional insights can now inform the emerging processes of implementation, regulation and practice of mitochondrial interventions.
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Affiliation(s)
- Erica Haimes
- PEALS (Policy, Ethics and Life Sciences) Research Centre, Newcastle University, 4th Floor Claremont Bridge, Claremont Road, Newcastle upon Tyne, NE1 7RU UK
| | - Ken Taylor
- PEALS (Policy, Ethics and Life Sciences) Research Centre, Newcastle University, 4th Floor Claremont Bridge, Claremont Road, Newcastle upon Tyne, NE1 7RU UK
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31
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Greenfield A, Braude P, Flinter F, Lovell-Badge R, Ogilvie C, Perry ACF. Assisted reproductive technologies to prevent human mitochondrial disease transmission. Nat Biotechnol 2017; 35:1059-1068. [PMID: 29121011 DOI: 10.1038/nbt.3997] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/02/2017] [Indexed: 12/31/2022]
Abstract
Mitochondria are essential cytoplasmic organelles that generate energy (ATP) by oxidative phosphorylation and mediate key cellular processes such as apoptosis. They are maternally inherited and in humans contain a 16,569-base-pair circular genome (mtDNA) encoding 37 genes required for oxidative phosphorylation. Mutations in mtDNA cause a range of pathologies, commonly affecting energy-demanding tissues such as muscle and brain. Because mitochondrial diseases are incurable, attention has focused on limiting the inheritance of pathogenic mtDNA by mitochondrial replacement therapy (MRT). MRT aims to avoid pathogenic mtDNA transmission between generations by maternal spindle transfer, pronuclear transfer or polar body transfer: all involve the transfer of nuclear DNA from an egg or zygote containing defective mitochondria to a corresponding egg or zygote with normal mitochondria. Here we review recent developments in animal and human models of MRT and the underlying biology. These have led to potential clinical applications; we identify challenges to their technical refinement.
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Affiliation(s)
- Andy Greenfield
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Harwell, Oxfordshire, UK
| | - Peter Braude
- Division of Women's Health, King's College, London, UK
| | - Frances Flinter
- Clinical Genetics Department, Guy's Hospital, Great Maze Pond, London, UK
| | | | - Caroline Ogilvie
- Genetics Department, Guy's & St Thomas' NHS Foundation Trust and Division of Women's Health, King's College, London, UK
| | - Anthony C F Perry
- Laboratory of Mammalian Molecular Embryology, Department of Biology and Biochemistry, University of Bath, Bath, UK
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32
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Mother's curse neutralizes natural selection against a human genetic disease over three centuries. Nat Ecol Evol 2017; 1:1400-1406. [PMID: 29046555 DOI: 10.1038/s41559-017-0276-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 06/06/2017] [Indexed: 12/30/2022]
Abstract
According to evolutionary theory, mitochondria could be poisoned gifts that mothers transmit to their sons. This is because mutations harmful to males are expected to accumulate in the mitochondrial genome, the so-called 'mother's curse'. However, the contribution of the mother's curse to the mutation load in nature remains largely unknown and hard to predict, because compensatory mechanisms could impede the spread of deleterious mitochondria. Here we provide evidence for the mother's curse in action over 290 years in a human population. We studied a mutation causing Leber's hereditary optical neuropathy, a disease with male-biased prevalence and which has long been suspected to be maintained in populations by the mother's curse. Male carriers showed a low fitness relative to non-carriers and to females, mostly explained by their high rate of infant mortality. Despite poor male fitness, selection analysis predicted a slight (albeit non-significant) increase in frequency, which sharply contrasts with the 35.5% per-generation decrease predicted if mitochondrial DNA transmission had been through males instead of females. Our results are therefore even suggestive of positive selection through the female line that may exacerbate effects of the mother's curse. This study supports a contribution of the mother's curse to the reduction of male lifespan, uncovering a large fitness effect associated with a single mitochondrial variant.
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33
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Caicedo A, Aponte PM, Cabrera F, Hidalgo C, Khoury M. Artificial Mitochondria Transfer: Current Challenges, Advances, and Future Applications. Stem Cells Int 2017; 2017:7610414. [PMID: 28751917 PMCID: PMC5511681 DOI: 10.1155/2017/7610414] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/30/2017] [Accepted: 05/15/2017] [Indexed: 12/18/2022] Open
Abstract
The objective of this review is to outline existing artificial mitochondria transfer techniques and to describe the future steps necessary to develop new therapeutic applications in medicine. Inspired by the symbiotic origin of mitochondria and by the cell's capacity to transfer these organelles to damaged neighbors, many researchers have developed procedures to artificially transfer mitochondria from one cell to another. The techniques currently in use today range from simple coincubations of isolated mitochondria and recipient cells to the use of physical approaches to induce integration. These methods mimic natural mitochondria transfer. In order to use mitochondrial transfer in medicine, we must answer key questions about how to replicate aspects of natural transport processes to improve current artificial transfer methods. Another priority is to determine the optimum quantity and cell/tissue source of the mitochondria in order to induce cell reprogramming or tissue repair, in both in vitro and in vivo applications. Additionally, it is important that the field explores how artificial mitochondria transfer techniques can be used to treat different diseases and how to navigate the ethical issues in such procedures. Without a doubt, mitochondria are more than mere cell power plants, as we continue to discover their potential to be used in medicine.
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Affiliation(s)
- Andrés Caicedo
- Colegio de Ciencias de la Salud, Escuela de Medicina, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Colegio de Ciencias Biológicas y Ambientales, Instituto de Microbiología, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Mito-Act Research Consortium, Quito, Ecuador
| | - Pedro M. Aponte
- Mito-Act Research Consortium, Quito, Ecuador
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
| | - Francisco Cabrera
- Mito-Act Research Consortium, Quito, Ecuador
- Colegio de Ciencias de la Salud, Escuela de Medicina Veterinaria, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Institute for Regenerative Medicine and Biotherapy (IRMB), INSERM U1183, 2 Montpellier University, Montpellier, France
| | - Carmen Hidalgo
- Mito-Act Research Consortium, Quito, Ecuador
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile
| | - Maroun Khoury
- Mito-Act Research Consortium, Quito, Ecuador
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile
- Consorcio Regenero, Chilean Consortium for Regenerative Medicine, Santiago, Chile
- Cells for Cells, Santiago, Chile
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34
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Vivian CJ, Brinker AE, Graw S, Koestler DC, Legendre C, Gooden GC, Salhia B, Welch DR. Mitochondrial Genomic Backgrounds Affect Nuclear DNA Methylation and Gene Expression. Cancer Res 2017; 77:6202-6214. [PMID: 28663334 DOI: 10.1158/0008-5472.can-17-1473] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 06/14/2017] [Accepted: 06/15/2017] [Indexed: 12/19/2022]
Abstract
Mitochondrial DNA (mtDNA) mutations and polymorphisms contribute to many complex diseases, including cancer. Using a unique mouse model that contains nDNA from one mouse strain and homoplasmic mitochondrial haplotypes from different mouse strain(s)-designated Mitochondrial Nuclear Exchange (MNX)-we showed that mtDNA could alter mammary tumor metastasis. Because retrograde and anterograde communication exists between the nuclear and mitochondrial genomes, we hypothesized that there are differential mtDNA-driven changes in nuclear (n)DNA expression and DNA methylation. Genome-wide nDNA methylation and gene expression were measured in harvested brain tissue from paired wild-type and MNX mice. Selective differential DNA methylation and gene expression were observed between strains having identical nDNA, but different mtDNA. These observations provide insights into how mtDNA could be altering epigenetic regulation and thereby contribute to the pathogenesis of metastasis. Cancer Res; 77(22); 6202-14. ©2017 AACR.
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Affiliation(s)
- Carolyn J Vivian
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, Kansas.,Heartland Center for Mitochondrial Medicine, Phoenix, Arizona
| | - Amanda E Brinker
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, Kansas.,Heartland Center for Mitochondrial Medicine, Phoenix, Arizona.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas
| | - Stefan Graw
- Department of Biostatistics, University of Kansas Medical Center, Kansas City, Kansas
| | - Devin C Koestler
- Department of Biostatistics, University of Kansas Medical Center, Kansas City, Kansas.,The University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, Kansas
| | | | | | - Bodour Salhia
- Translational Genomics Research Institute, Phoenix, Arizona
| | - Danny R Welch
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, Kansas. .,Heartland Center for Mitochondrial Medicine, Phoenix, Arizona.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas.,The University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, Kansas
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35
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Mitochondrial Replacement Therapy: Are Mito-nuclear Interactions Likely To Be a Problem? Genetics 2017; 205:1365-1372. [PMID: 28360127 DOI: 10.1534/genetics.116.196436] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 02/08/2017] [Indexed: 02/01/2023] Open
Abstract
It has been suggested that deleterious interactions between the mitochondrial and nuclear genomes could pose a problem for mitochondrial replacement therapy (MRT). This is because the mitochondrial genome is placed in a novel nuclear environment using this technique. In contrast, it is inherited with half the mother's genome during normal reproduction, a genome that it is relatively compatible with, since the mother is alive. Here, I review the evidence of whether mito-nuclear interactions are likely to pose a problem for MRT. The majority of the available experimental evidence, both in humans and other species, suggests that MRT is not harmful. These results are consistent with population genetic theory, which predicts that deleterious mito-nuclear interactions are unlikely to be much more prevalent in individuals born to MRT than normal reproduction, particularly in a species such as humans with low population differentiation. This is because selection is unlikely to be strong enough to establish significant linkage disequilibrium between the mitochondrial and nuclear genomes. These results are supported by a meta-analysis of 231 cases, from a variety of animals, in which the mitochondrial DNA (mtDNA) from one strain has been introgressed into the nuclear background of another strain of the same species. Overall, there is little tendency for introgression of mtDNA to be harmful.
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36
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Abstract
It has been suggested that deleterious interactions between the mitochondrial and nuclear genomes could pose a problem for mitochondrial replacement therapy (MRT). This is because the mitochondrial genome is placed in a novel nuclear environment using this technique. In contrast, it is inherited with half the mother's genome during normal reproduction, a genome that it is relatively compatible with, since the mother is alive. Here, I review the evidence of whether mito-nuclear interactions are likely to pose a problem for MRT. The majority of the available experimental evidence, both in humans and other species, suggests that MRT is not harmful. These results are consistent with population genetic theory, which predicts that deleterious mito-nuclear interactions are unlikely to be much more prevalent in individuals born to MRT than normal reproduction, particularly in a species such as humans with low population differentiation. This is because selection is unlikely to be strong enough to establish significant linkage disequilibrium between the mitochondrial and nuclear genomes. These results are supported by a meta-analysis of 231 cases, from a variety of animals, in which the mitochondrial DNA (mtDNA) from one strain has been introgressed into the nuclear background of another strain of the same species. Overall, there is little tendency for introgression of mtDNA to be harmful.
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Affiliation(s)
- Adam Eyre-Walker
- School of Life Sciences, University of Sussex, Brighton BN1 9QG, United Kingdom
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37
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Rishishwar L, Jordan IK. Implications of human evolution and admixture for mitochondrial replacement therapy. BMC Genomics 2017; 18:140. [PMID: 28178941 PMCID: PMC5299762 DOI: 10.1186/s12864-017-3539-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/02/2017] [Indexed: 11/15/2022] Open
Abstract
Background Mitochondrial replacement (MR) therapy is a new assisted reproductive technology that allows women with mitochondrial disorders to give birth to healthy children by combining their nuclei with mitochondria from unaffected egg donors. Evolutionary biologists have raised concerns about the safety of MR therapy based on the extent to which nuclear and mitochondrial genomes are observed to co-evolve within natural populations, i.e. the nuclear-mitochondrial mismatch hypothesis. In support of this hypothesis, a number of previous studies on model organisms have provided evidence for incompatibility between nuclear and mitochondrial genomes from divergent populations of the same species. Results We tested the nuclear-mitochondrial mismatch hypothesis for humans by observing the extent of naturally occurring nuclear-mitochondrial mismatch seen for 2,504 individuals across 26 populations, from 5 continental populations groups, characterized as part of the 1000 Genomes Project (1KGP). We also performed a replication analysis on mitochondrial DNA (mtDNA) haplotypes for 1,043 individuals from 58 populations, characterized as part of the Human Genome Diversity Project (HGDP). Nuclear DNA (nDNA) and mtDNA sequences from the 1KGP were directly compared within and between populations, and the population distributions of mtDNA haplotypes derived from both sequence (1KGP) and genotype (HGDP) data were evaluated. Levels of nDNA and mtDNA pairwise sequence divergence are highly correlated, consistent with their co-evolution among human populations. However, there are numerous cases of co-occurrence of nuclear and mitochondrial genomes from divergent populations within individual humans. Furthermore, pairs of individuals with closely related nuclear genomes can have highly divergent mtDNA haplotypes. Supposedly mismatched nuclear-mitochondrial genome combinations are found not only within individuals from populations known to be admixed, where they may be expected, but also from populations with low overall levels of observed admixture. Conclusions These results show that mitochondrial and nuclear genomes from divergent human populations can co-exist within healthy individuals, indicating that mismatched nDNA-mtDNA combinations are not deleterious or subject to purifying selection. Accordingly, human nuclear-mitochondrial mismatches are not likely to jeopardize the safety of MR therapy. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3539-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lavanya Rishishwar
- School of Biology, Georgia Institute of Technology, Atlanta, GA, USA.,PanAmerican Bioinformatics Institute, Cali, Colombia.,Applied Bioinformatics Laboratory, Atlanta, GA, USA
| | - I King Jordan
- School of Biology, Georgia Institute of Technology, Atlanta, GA, USA. .,PanAmerican Bioinformatics Institute, Cali, Colombia. .,Applied Bioinformatics Laboratory, Atlanta, GA, USA.
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38
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Reznichenko AS, Huyser C, Pepper MS. Mitochondrial transfer: Implications for assisted reproductive technologies. Appl Transl Genom 2016; 11:40-47. [PMID: 28018848 PMCID: PMC5167373 DOI: 10.1016/j.atg.2016.10.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 10/05/2016] [Accepted: 10/14/2016] [Indexed: 01/24/2023]
Abstract
The use of mitochondrial transfer as a clinic procedure is drawing closer to reality. Here we provide a detailed overview of mitochondrial transfer techniques – both established and recent – including pronuclear, spindle, ooplasmic and blastomere transfer. Reasons as to why some techniques are more suitable for the prevention of mitochondrial DNA disease than others, as well as the advantages and disadvantages of each methodology, are discussed. The possible clinical introduction of these techniques has raised concerns about the adverse effects they may have on resultant embryos and offspring. Success rates of each technique, embryo viability and developmental consequences post mitochondrial transfer are addressed through analysis of evidence obtained from both animal and human studies. Counterarguments against potential mitochondrial-nuclear genome incompatibility are also provided. Additional clinical applications of mitochondrial transfer techniques are discussed. These include the rescue or enhancement of fertility in women of advanced maternal age or those suffering from diabetes. An alternative to using mitochondrial DNA transfer for germ line therapies is the therapeutic use of somatic cell nuclear transfer for the generation of personalised stem cells. Although ethically challenging, this method could offer patients already suffering from mitochondrial DNA diseases a novel treatment option.
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Affiliation(s)
- A S Reznichenko
- IVF Laboratory, Medfem Fertility Clinic, Bryanston, South Africa
| | - C Huyser
- Department of Obstetrics and Gynaecology, University of Pretoria, Steve Biko Academic Hospital, Pretoria, South Africa
| | - M S Pepper
- Department of Immunology and Institute for Cellular and Molecular Medicine, and SAMRC Extramural Unit doe Stem Cell Research and Therapy, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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39
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Sloan DB, Fields PD, Havird JC. Mitonuclear linkage disequilibrium in human populations. Proc Biol Sci 2016; 282:rspb.2015.1704. [PMID: 26378221 DOI: 10.1098/rspb.2015.1704] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
There is extensive evidence from model systems that disrupting associations between co-adapted mitochondrial and nuclear genotypes can lead to deleterious and even lethal consequences. While it is tempting to extrapolate from these observations and make inferences about the human-health effects of altering mitonuclear associations, the importance of such associations may vary greatly among species, depending on population genetics, demographic history and other factors. Remarkably, despite the extensive study of human population genetics, the statistical associations between nuclear and mitochondrial alleles remain largely uninvestigated. We analysed published population genomic data to test for signatures of historical selection to maintain mitonuclear associations, particularly those involving nuclear genes that encode mitochondrial-localized proteins (N-mt genes). We found that significant mitonuclear linkage disequilibrium (LD) exists throughout the human genome, but these associations were generally weak, which is consistent with the paucity of population genetic structure in humans. Although mitonuclear LD varied among genomic regions (with especially high levels on the X chromosome), N-mt genes were statistically indistinguishable from background levels, suggesting that selection on mitonuclear epistasis has not preferentially maintained associations involving this set of loci at a species-wide level. We discuss these findings in the context of the ongoing debate over mitochondrial replacement therapy.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Peter D Fields
- Zoological Institute, University of Basel, Vesalgasse 1, Basel, 4051, Switzerland
| | - Justin C Havird
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
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Incompatibility between Nuclear and Mitochondrial Genomes Contributes to an Interspecies Reproductive Barrier. Cell Metab 2016; 24:283-94. [PMID: 27425585 PMCID: PMC4981548 DOI: 10.1016/j.cmet.2016.06.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 03/29/2016] [Accepted: 06/17/2016] [Indexed: 11/22/2022]
Abstract
Vertebrate cells carry two different genomes, nuclear (nDNA) and mitochondrial (mtDNA), both encoding proteins involved in oxidative phosphorylation. Because of the extensive interactions, adaptive coevolution of the two genomes must occur to ensure normal mitochondrial function. To investigate whether incompatibilities between these two genomes could contribute to interspecies reproductive barriers, we performed reciprocal mtDNA replacement (MR) in zygotes between widely divergent Mus m. domesticus (B6) and conplastic Mus m. musculus (PWD) mice. Transfer of MR1 cybrid embryos (B6nDNA-PWDmtDNA) supported normal development of F1 offspring with reduced male fertility but unaffected reproductive fitness in females. Furthermore, donor PWD mtDNA was faithfully transmitted through the germline into F2 and F3 generations. In contrast, reciprocal MR2 (PWDnDNA-B6mtDNA) produced high embryonic loss and stillborn rates, suggesting an association between mitochondrial function and infertility. These results strongly suggest that functional incompatibility between nuclear and mitochondrial genomes contributes to interspecies reproductive isolation in mammals.
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Latorre-Pellicer A, Moreno-Loshuertos R, Lechuga-Vieco AV, Sánchez-Cabo F, Torroja C, Acín-Pérez R, Calvo E, Aix E, González-Guerra A, Logan A, Bernad-Miana ML, Romanos E, Cruz R, Cogliati S, Sobrino B, Carracedo Á, Pérez-Martos A, Fernández-Silva P, Ruíz-Cabello J, Murphy MP, Flores I, Vázquez J, Enríquez JA. Mitochondrial and nuclear DNA matching shapes metabolism and healthy ageing. Nature 2016; 535:561-5. [PMID: 27383793 DOI: 10.1038/nature18618] [Citation(s) in RCA: 288] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/02/2016] [Indexed: 12/25/2022]
Abstract
Human mitochondrial DNA (mtDNA) shows extensive within population sequence variability. Many studies suggest that mtDNA variants may be associated with ageing or diseases, although mechanistic evidence at the molecular level is lacking. Mitochondrial replacement has the potential to prevent transmission of disease-causing oocyte mtDNA. However, extension of this technology requires a comprehensive understanding of the physiological relevance of mtDNA sequence variability and its match with the nuclear-encoded mitochondrial genes. Studies in conplastic animals allow comparison of individuals with the same nuclear genome but different mtDNA variants, and have provided both supporting and refuting evidence that mtDNA variation influences organismal physiology. However, most of these studies did not confirm the conplastic status, focused on younger animals, and did not investigate the full range of physiological and phenotypic variability likely to be influenced by mitochondria. Here we systematically characterized conplastic mice throughout their lifespan using transcriptomic, proteomic,metabolomic, biochemical, physiological and phenotyping studies. We show that mtDNA haplotype profoundly influences mitochondrial proteostasis and reactive oxygen species generation,insulin signalling, obesity, and ageing parameters including telomere shortening and mitochondrial dysfunction, resulting in profound differences in health longevity between conplastic strains.
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Yu-Wai-Man P. Genetic manipulation for inherited neurodegenerative diseases: myth or reality? Br J Ophthalmol 2016; 100:1322-31. [PMID: 27002113 PMCID: PMC5050284 DOI: 10.1136/bjophthalmol-2015-308329] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 02/28/2016] [Indexed: 12/22/2022]
Abstract
Rare genetic diseases affect about 7% of the general population and over 7000 distinct clinical syndromes have been described with the majority being due to single gene defects. This review will provide a critical overview of genetic strategies that are being pioneered to halt or reverse disease progression in inherited neurodegenerative diseases. This field of research covers a vast area and only the most promising treatment paradigms will be discussed with a particular focus on inherited eye diseases, which have paved the way for innovative gene therapy paradigms, and mitochondrial diseases, which are currently generating a lot of debate centred on the bioethics of germline manipulation.
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Affiliation(s)
- Patrick Yu-Wai-Man
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK
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Mitochondria in pluripotent stem cells: stemness regulators and disease targets. Curr Opin Genet Dev 2016; 38:1-7. [PMID: 26953561 DOI: 10.1016/j.gde.2016.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/01/2016] [Accepted: 02/05/2016] [Indexed: 11/23/2022]
Abstract
Beyond their canonical role in efficient ATP production through oxidative metabolism, mitochondria are increasingly recognized as critical in defining stem cell function and fate. Implicating a fundamental interplay within the epigenetics of eukaryotic cell systems, the integrity of mitochondria is found vital across the developmental/differentiation spectrum from securing pluripotency maintenance to informing organotypic decisions. This overview will discuss recent progress on examining the plasticity of mitochondria in enabling the execution of programming and reprogramming regimens, as well as the application of nuclear reprogramming and somatic cell nuclear transfer as rescue techniques to generate genetically and functionally corrected pluripotent stem cells from patients with mitochondrial DNA-based disease.
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Richardson J, Irving L, Hyslop LA, Choudhary M, Murdoch A, Turnbull DM, Herbert M. Concise reviews: Assisted reproductive technologies to prevent transmission of mitochondrial DNA disease. Stem Cells 2015; 33:639-45. [PMID: 25377180 PMCID: PMC4359624 DOI: 10.1002/stem.1887] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 09/26/2014] [Accepted: 10/11/2014] [Indexed: 12/31/2022]
Abstract
While the fertilized egg inherits its nuclear DNA from both parents, the mitochondrial DNA is strictly maternally inherited. Cells contain multiple copies of mtDNA, each of which encodes 37 genes, which are essential for energy production by oxidative phosphorylation. Mutations can be present in all, or only in some copies of mtDNA. If present above a certain threshold, pathogenic mtDNA mutations can cause a range of debilitating and fatal diseases. Here, we provide an update of currently available options and new techniques under development to reduce the risk of transmitting mtDNA disease from mother to child. Preimplantation genetic diagnosis (PGD), a commonly used technique to detect mutations in nuclear DNA, is currently being offered to determine the mutation load of embryos produced by women who carry mtDNA mutations. The available evidence indicates that cells removed from an eight-cell embryo are predictive of the mutation load in the entire embryo, indicating that PGD provides an effective risk reduction strategy for women who produce embryos with low mutation loads. For those who do not, research is now focused on meiotic nuclear transplantation techniques to uncouple the inheritance of nuclear and mtDNA. These approaches include transplantation of any one of the products or female meiosis (meiosis II spindle, or either of the polar bodies) between oocytes, or the transplantation of pronuclei between fertilized eggs. In all cases, the transferred genetic material arises from a normal meiosis and should therefore, not be confused with cloning. The scientific progress and associated regulatory issues are discussed. Stem Cells2015;33:639–645
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Affiliation(s)
- Jessica Richardson
- Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, United Kingdom; Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
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45
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Stewart JB, Chinnery PF. The dynamics of mitochondrial DNA heteroplasmy: implications for human health and disease. Nat Rev Genet 2015; 16:530-42. [PMID: 26281784 DOI: 10.1038/nrg3966] [Citation(s) in RCA: 634] [Impact Index Per Article: 63.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Common genetic variants of mitochondrial DNA (mtDNA) increase the risk of developing several of the major health issues facing the western world, including neurodegenerative diseases. In this Review, we consider how these mtDNA variants arose and how they spread from their origin on one single molecule in a single cell to be present at high levels throughout a specific organ and, ultimately, to contribute to the population risk of common age-related disorders. mtDNA persists in all aerobic eukaryotes, despite a high substitution rate, clonal propagation and little evidence of recombination. Recent studies have found that de novo mtDNA mutations are suppressed in the female germ line; despite this, mtDNA heteroplasmy is remarkably common. The demonstration of a mammalian mtDNA genetic bottleneck explains how new germline variants can increase to high levels within a generation, and the ultimate fixation of less-severe mutations that escape germline selection explains how they can contribute to the risk of late-onset disorders.
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Affiliation(s)
- James B Stewart
- Max Planck Institute for Biology of Ageing, Cologne 50931, Germany
| | - Patrick F Chinnery
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 1BZ, UK
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46
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47
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Ma H, Folmes CDL, Wu J, Morey R, Mora-Castilla S, Ocampo A, Ma L, Poulton J, Wang X, Ahmed R, Kang E, Lee Y, Hayama T, Li Y, Van Dyken C, Gutierrez NM, Tippner-Hedges R, Koski A, Mitalipov N, Amato P, Wolf DP, Huang T, Terzic A, Laurent LC, Izpisua Belmonte JC, Mitalipov S. Metabolic rescue in pluripotent cells from patients with mtDNA disease. Nature 2015; 524:234-8. [PMID: 26176921 DOI: 10.1038/nature14546] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 05/12/2015] [Indexed: 12/11/2022]
Abstract
Mitochondria have a major role in energy production via oxidative phosphorylation, which is dependent on the expression of critical genes encoded by mitochondrial (mt)DNA. Mutations in mtDNA can cause fatal or severely debilitating disorders with limited treatment options. Clinical manifestations vary based on mutation type and heteroplasmy (that is, the relative levels of mutant and wild-type mtDNA within each cell). Here we generated genetically corrected pluripotent stem cells (PSCs) from patients with mtDNA disease. Multiple induced pluripotent stem (iPS) cell lines were derived from patients with common heteroplasmic mutations including 3243A>G, causing mitochondrial encephalomyopathy and stroke-like episodes (MELAS), and 8993T>G and 13513G>A, implicated in Leigh syndrome. Isogenic MELAS and Leigh syndrome iPS cell lines were generated containing exclusively wild-type or mutant mtDNA through spontaneous segregation of heteroplasmic mtDNA in proliferating fibroblasts. Furthermore, somatic cell nuclear transfer (SCNT) enabled replacement of mutant mtDNA from homoplasmic 8993T>G fibroblasts to generate corrected Leigh-NT1 PSCs. Although Leigh-NT1 PSCs contained donor oocyte wild-type mtDNA (human haplotype D4a) that differed from Leigh syndrome patient haplotype (F1a) at a total of 47 nucleotide sites, Leigh-NT1 cells displayed transcriptomic profiles similar to those in embryo-derived PSCs carrying wild-type mtDNA, indicative of normal nuclear-to-mitochondrial interactions. Moreover, genetically rescued patient PSCs displayed normal metabolic function compared to impaired oxygen consumption and ATP production observed in mutant cells. We conclude that both reprogramming approaches offer complementary strategies for derivation of PSCs containing exclusively wild-type mtDNA, through spontaneous segregation of heteroplasmic mtDNA in individual iPS cell lines or mitochondrial replacement by SCNT in homoplasmic mtDNA-based disease.
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Affiliation(s)
- Hong Ma
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Clifford D L Folmes
- Center for Regenerative Medicine and Department of Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Jun Wu
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Robert Morey
- Department of Reproductive Medicine, University of California, San Diego, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA
| | - Sergio Mora-Castilla
- Department of Reproductive Medicine, University of California, San Diego, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA
| | - Alejandro Ocampo
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Li Ma
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Joanna Poulton
- Department of Obstetrics and Gynaecology, John Radcliffe Hospital, University of Oxford, Headington, Oxford OX3 9DU, UK
| | - Xinjian Wang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
| | - Riffat Ahmed
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Eunju Kang
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Yeonmi Lee
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Tomonari Hayama
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Ying Li
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Crystal Van Dyken
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Nuria Marti Gutierrez
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Rebecca Tippner-Hedges
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Amy Koski
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Nargiz Mitalipov
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Paula Amato
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Oregon Health and Science University, 3181 Southwest Sam Jackson Park Road, Portland, Oregon 97239, USA
| | - Don P Wolf
- Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
| | - Andre Terzic
- Center for Regenerative Medicine and Department of Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Louise C Laurent
- Department of Reproductive Medicine, University of California, San Diego, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, California 92037, USA
| | - Juan Carlos Izpisua Belmonte
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Shoukhrat Mitalipov
- 1] Center for Embryonic Cell and Gene Therapy, Oregon Health &Science University, 3303 S.W. Bond Avenue, Portland, Oregon 97239, USA [2] Division of Reproductive &Developmental Sciences, Oregon National Primate Research Center, Oregon Health &Science University, 505 N.W. 185th Avenue, Beaverton, Oregon 97006, USA
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48
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Otten ABC, Smeets HJM. Evolutionary defined role of the mitochondrial DNA in fertility, disease and ageing. Hum Reprod Update 2015; 21:671-89. [PMID: 25976758 DOI: 10.1093/humupd/dmv024] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 04/22/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The endosymbiosis of an alpha-proteobacterium and a eubacterium a billion years ago paved the way for multicellularity and enabled eukaryotes to flourish. The selective advantage for the host was the acquired ability to generate large amounts of intracellular hydrogen-dependent adenosine triphosphate. The price was increased reactive oxygen species (ROS) inside the eukaryotic cell, causing high mutation rates of the mitochondrial DNA (mtDNA). According to the Muller's ratchet theory, this accumulation of mutations in asexually transmitted mtDNA would ultimately lead to reduced reproductive fitness and eventually extinction. However, mitochondria have persisted over the course of evolution, initially due to a rapid, extreme evolutionary reduction of the mtDNA content. After the phylogenetic divergence of eukaryotes into animals, fungi and plants, differences in evolution of the mtDNA occurred with different adaptations for coping with the mutation burden within these clades. As a result, mitochondrial evolutionary mechanisms have had a profound effect on human adaptation, fertility, healthy reproduction, mtDNA disease manifestation and transmission and ageing. An understanding of these mechanisms might elucidate novel approaches for treatment and prevention of mtDNA disease. METHODS The scientific literature was investigated to determine how mtDNA evolved in animals, plants and fungi. Furthermore, the different mechanisms of mtDNA inheritance and of balancing Muller's ratchet in these species were summarized together with the consequences of these mechanisms for human health and reproduction. RESULTS Animal, plant and fungal mtDNA have evolved differently. Animals have compact genomes, little recombination, a stable number of genes and a high mtDNA copy number, whereas plants have larger genomes with variable gene counts, a low mtDNA copy number and many recombination events. Fungal mtDNA is somewhere in between. In plants, the mtDNA mutation rate is kept low by effective ROS defence and efficient recombination-mediated mtDNA repair. In animal mtDNA, these mechanisms are not or less well-developed and the detrimental mutagenesis events are controlled by a high mtDNA copy number in combination with a genetic bottleneck and purifying selection during transmission. The mtDNA mutation rates in animals are higher than in plants, which allow mobile animals to adapt more rapidly to various environmental conditions in terms of energy production, whereas static plants do not have this need. Although at the level of the species, these mechanisms have been extremely successful, they can have adverse effects for the individual, resulting, in humans, in severe or unpredictably segregating mtDNA diseases, as well as fertility problems and unhealthy ageing. CONCLUSIONS Understanding the forces and processes that underlie mtDNA evolution among different species increases our knowledge on the detrimental consequences that individuals can have from these evolutionary end-points. Alternative outcomes in animals, fungi and plants will lead to a better understanding of the inheritance of mtDNA disorders and mtDNA-related fertility problems. These will allow the development of options to ameliorate, cure and/or prevent mtDNA diseases and mtDNA-related fertility problems.
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Affiliation(s)
- Auke B C Otten
- Department of Clinical Genetics, Unit Clinical Genomics, Maastricht University Medical Centre, PO box 616 (box 16), 6200 MD Maastricht, The Netherlands School for Oncology and Developmental Biology (GROW), Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Hubert J M Smeets
- Department of Clinical Genetics, Unit Clinical Genomics, Maastricht University Medical Centre, PO box 616 (box 16), 6200 MD Maastricht, The Netherlands School for Oncology and Developmental Biology (GROW), Maastricht University Medical Centre, Maastricht, The Netherlands
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49
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Herbert M, Turnbull D. Mitochondrial replacement to prevent the transmission of mitochondrial DNA disease. EMBO Rep 2015; 16:539-40. [PMID: 25888328 PMCID: PMC4428042 DOI: 10.15252/embr.201540354] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Mary Herbert
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Doug Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
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50
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Leigh PN, Al-Sarraj S, DiMauro S. Impact commentaries. Subacute necrotising encephalomyelopathy (Leigh's disease; Leigh syndrome). J Neurol Neurosurg Psychiatry 2015; 86:363-5. [PMID: 25587071 DOI: 10.1136/jnnp-2012-304601] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- P N Leigh
- Brighton and Sussex Medical School, Trafford Centre for Biomedical Science, University of Sussex, East Sussex, UK Department of Basic and Clinical Neuroscience, King's College London, London, UK
| | - S Al-Sarraj
- Department of Neuropathology, King's College Hospital NHS Foundation Trust, London, UK
| | - S DiMauro
- Department of Neurology, Columbia University Medical Center, New York, USA
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