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Helgudóttir SS, Mørkholt AS, Lichota J, Bruun-Nyzell P, Andersen MC, Kristensen NMJ, Johansen AK, Zinn MR, Jensdóttir HM, Nieland JDV. Rethinking neurodegenerative diseases: neurometabolic concept linking lipid oxidation to diseases in the central nervous system. Neural Regen Res 2024; 19:1437-1445. [PMID: 38051885 PMCID: PMC10883494 DOI: 10.4103/1673-5374.387965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 09/21/2023] [Indexed: 12/07/2023] Open
Abstract
ABSTRACT Currently, there is a lack of effective medicines capable of halting or reversing the progression of neurodegenerative disorders, including amyotrophic lateral sclerosis, Parkinson's disease, multiple sclerosis, or Alzheimer's disease. Given the unmet medical need, it is necessary to reevaluate the existing paradigms of how to target these diseases. When considering neurodegenerative diseases from a systemic neurometabolic perspective, it becomes possible to explain the shared pathological features. This innovative approach presented in this paper draws upon extensive research conducted by the authors and researchers worldwide. In this review, we highlight the importance of metabolic mitochondrial dysfunction in the context of neurodegenerative diseases. We provide an overview of the risk factors associated with developing neurodegenerative disorders, including genetic, epigenetic, and environmental factors. Additionally, we examine pathological mechanisms implicated in these diseases such as oxidative stress, accumulation of misfolded proteins, inflammation, demyelination, death of neurons, insulin resistance, dysbiosis, and neurotransmitter disturbances. Finally, we outline a proposal for the restoration of mitochondrial metabolism, a crucial aspect that may hold the key to facilitating curative therapeutic interventions for neurodegenerative disorders in forthcoming advancements.
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Affiliation(s)
| | | | - Jacek Lichota
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | | | - Mads Christian Andersen
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Nanna Marie Juhl Kristensen
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Amanda Krøger Johansen
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Mikela Reinholdt Zinn
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Hulda Maria Jensdóttir
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - John Dirk Vestergaard Nieland
- 2N Pharma ApS, NOVI Science Park, Aalborg, Denmark
- Molecular Pharmacology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
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Bene Watts S, Gauthier B, Erickson AC, Morrison J, Sebastian M, Gillman L, McIntosh S, Ens C, Sherwin E, McCormick R, Sanatani S, Arbour L. A mild phenotype associated with KCNQ1 p.V205M mediated long QT syndrome in First Nations children of Northern British Columbia: effect of additional variants and considerations for management. Front Pediatr 2024; 12:1394105. [PMID: 38884101 PMCID: PMC11176454 DOI: 10.3389/fped.2024.1394105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 05/16/2024] [Indexed: 06/18/2024] Open
Abstract
Introduction Congenital Long QT Syndrome (LQTS) is common in a First Nations community in Northern British Columbia due to the founder variant KCNQ1 p.V205M. Although well characterized molecularly and clinically in adults, no data have been previously reported on the pediatric population. The phenotype in adults has been shown to be modified by a splice site variant in KCNQ1 (p.L353L). The CPT1A p.P479L metabolic variant, also common in Northern Indigenous populations, is associated with hypoglycemia and infant death. Since hypoglycemia can affect the corrected QT interval (QTc) and may confer risk for seizures (also associated with LQTS), we sought to determine the effect of all three variants on the LQTS phenotype in children within our First Nations cohort. Methods As part of a larger study assessing those with LQTS and their relatives in a Northern BC First Nation, we assessed those entering the study from birth to age 18 years. We compared the corrected peak QTc and potential cardiac events (syncope/seizures) of 186 children from birth to 18 years, with and without the KCNQ1 (p.V205M and p.L353L) and CPT1A variants, alone and in combination. Linear and logistic regression and student t-tests were applied as appropriate. Results Only the KCNQ1 p.V205M variant conferred a significant increase in peak QTc 23.8 ms (p < 0.001) above baseline, with females increased by 30.1 ms (p < 0.001) and males by 18.9 ms (p < 0.01). There was no evidence of interaction effects with the other two variants studied. Although the p.V205M variant was not significantly associated with syncope/seizures, the odds of having a seizure/syncope were significantly increased for those homozygous for CPT1A p.P479L compared to homozygous wild type (Odds Ratio [OR]3.0 [95% confidence interval (CI) 1.2-7.7]; p = 0.019). Conclusion While the KCNQ1 p.V205M variant prolongs the peak QTc, especially in females, the CPT1A p.P479L variant is more strongly associated with loss of consciousness events. These findings suggest that effect of the KCNQ1 p.V205M variant is mild in this cohort, which may have implications for standard management. Our findings also suggest the CPT1A p.P479L variant is a risk factor for seizures and possibly syncope, which may mimic a long QT phenotype.
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Affiliation(s)
- Simona Bene Watts
- Island Medical Program, University of British Columbia, Victoria, BC, Canada
| | - Barbara Gauthier
- Epidemiology and Surveillance Unit, Interior Health Authority, Kelowna, BC, Canada
| | | | | | | | - Lawrence Gillman
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Sarah McIntosh
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Connie Ens
- Department of Pediatrics, Division of Cardiology, British Columbia Children's Hospital, Vancouver, BC, Canada
| | - Elizabeth Sherwin
- Department of Pediatrics, Children's National Hospital, Washington, DC, United States
| | - Rod McCormick
- Department of Education and Social Work, Thompson Rivers University, Kamloops, BC, Canada
| | - Shubhayan Sanatani
- Department of Pediatrics, Division of Cardiology, British Columbia Children's Hospital, Vancouver, BC, Canada
| | - Laura Arbour
- Island Medical Program, University of British Columbia, Victoria, BC, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
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3
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Stratakis CA. Genes and environment: An old pair in a new era. Maturitas 2023; 178:107851. [PMID: 37806009 DOI: 10.1016/j.maturitas.2023.107851] [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: 08/22/2023] [Accepted: 09/16/2023] [Indexed: 10/10/2023]
Abstract
What is the relationship between our genes and the environment we live in with regard to health? Like the debate about nature or nurture in the determination of our personality and behavior, the issue of genes and environment has been discussed intensely in the last two centuries. Is it Darwin or Lamarck who is right about the basic determinants of our health, especially as we age in a rapidly changing environment? Evolutionary biology as proposed by Darwin with natural selection at its core may not be able to explain almost instant adjustments of phenotypic traits to the pressures of the environment. Epigenesis, a concept that dates from Aristotle, provides a mechanism for the environment to affect variation in genetic traits that may become heritable. Indeed, Lamarck first described the inheritance of acquired characteristics. Thus, it appears that in contemporary genetics, both Darwin and Lamarck are right: environmental pressures may affect our genes through epigenetics, in ways that allow for inheritance of the changes, a Lamarckian concept; however, evolution through natural selection is the basis for incorporation (or rejection) of new traits and their sustained inheritance, a Darwinian concept. In this review, we present the synthesis of Darwin's and Lamarck's theories, the only way to understand how our health, and that of our progeny, responds to challenging and fast-changing environmental cues. In addition, we present other examples of environment-driven changes in disease frequency or expression.
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Affiliation(s)
- Constantine A Stratakis
- NIH Clinical Center, NICHD, NIH, Bethesda, MD, USA; Research, Human Genetics & Precision Medicine, IMBB, FORTH, Heraklion, Greece; Medical Genetics, H. Dunant Hospital, Athens, Greece; Science Board, ELPEN Research Institute, Athens, Greece; European University of Cyprus, Medical School, Nicosia, Cyprus.
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4
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Beans JA, Trinidad SB, Shane AL, Wark KA, Avey JP, Apok C, Guinn T, Robler SK, Hirschfeld M, Koeller DM, Dillard DA. The CPT1A Arctic variant: perspectives of community members and providers in two Alaska tribal health settings. J Community Genet 2023; 14:613-620. [PMID: 37847346 PMCID: PMC10725401 DOI: 10.1007/s12687-023-00684-6] [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: 02/04/2023] [Accepted: 10/06/2023] [Indexed: 10/18/2023] Open
Abstract
Newborn screening in Alaska includes screening for carnitine palmitoyltransferase 1A (CPT1A) deficiency. The CPT1A Arctic variant is a variant highly prevalent among Indigenous peoples in the Arctic. In this study, we sought to elicit Alaska Native (AN) community member and AN-serving healthcare providers' knowledge and perspectives on the CPT1A Arctic variant. Focus groups with community members and healthcare providers were held in two regions of Alaska between October 2018 and January 2019. Thematic analysis was used to identify recurring constructs. Knowledge and understanding about the CPT1A Arctic variant and its health impact varied, and participants were interested in learning more about it. Additional education for healthcare professionals was recommended to improve providers' ability to communicate with family caregivers about the Arctic variant. Engagement with AN community members identified opportunities to improve educational outreach via multiple modalities for providers and caregivers on the Arctic variant, which could help to increase culturally relevant guidance and avoid stigmatization, undue worry, and unnecessary intervention. Education and guidance on the care of infants and children homozygous for the CPT1A Arctic variant could improve care and reduce negative psychosocial effects.
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Affiliation(s)
- Julie A Beans
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA.
| | - Susan Brown Trinidad
- Department of Bioethics & Humanities, University of Washington, Seattle, WA, USA
| | - Aliassa L Shane
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA
| | - Kyle A Wark
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA
| | - Jaedon P Avey
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA
| | | | - Tiffany Guinn
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA
| | | | - Matthew Hirschfeld
- Maternal Child Health Services, Alaska Native Medical Center, Anchorage, AK, USA
| | - David M Koeller
- Department of Molecular & Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | - Denise A Dillard
- Research and Data Services Department, Southcentral Foundation, Anchorage, AK, USA
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5
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Neutrophil trafficking to the site of infection requires Cpt1a-dependent fatty acid β-oxidation. Commun Biol 2022; 5:1366. [PMID: 36513703 PMCID: PMC9747976 DOI: 10.1038/s42003-022-04339-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
Cellular metabolism influences immune cell function, with mitochondrial fatty acid β-oxidation and oxidative phosphorylation required for multiple immune cell phenotypes. Carnitine palmitoyltransferase 1a (Cpt1a) is considered the rate-limiting enzyme for mitochondrial metabolism of long-chain fatty acids, and Cpt1a deficiency is associated with infant mortality and infection risk. This study was undertaken to test the hypothesis that impairment in Cpt1a-dependent fatty acid oxidation results in increased susceptibility to infection. Screening the Cpt1a gene for common variants predicted to affect protein function revealed allele rs2229738_T, which was associated with pneumonia risk in a targeted human phenome association study. Pharmacologic inhibition of Cpt1a increases mortality and impairs control of the infection in a murine model of bacterial pneumonia. Susceptibility to pneumonia is associated with blunted neutrophilic responses in mice and humans that result from impaired neutrophil trafficking to the site of infection. Chemotaxis responsible for neutrophil trafficking requires Cpt1a-dependent mitochondrial fatty acid oxidation for amplification of chemoattractant signals. These findings identify Cpt1a as a potential host determinant of infection susceptibility and demonstrate a requirement for mitochondrial fatty acid oxidation in neutrophil biology.
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6
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Wilson C. Metabolic disease in the Pacific: Lessons for indigenous populations. J Inherit Metab Dis 2022; 45:919-925. [PMID: 35267200 DOI: 10.1002/jimd.12495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/02/2022] [Accepted: 03/08/2022] [Indexed: 11/09/2022]
Abstract
Twenty-five percent of the New Zealand population is either Māori or Pacific and are thus indigenous to the region. The New Zealand National Metabolic Service has considerable experience in diagnosing and managing metabolic diseases in this population. The frequencies and phenotypes of inborn errors of metabolism in indigenous people differ from that in Western European populations. Metabolic services need to be aware of these local variations and adapt their screening and treatment protocols accordingly. Likewise, the services themselves need to adopt culturally appropriate practices. This includes an understanding of the language, ideally employment of indigenous people and targeting of the service to meet the needs of the people. Knowledge of the metabolic diseases common within particular ethnic groups is important for the rapid delivery of appropriate management. Newborn screening protocols need to reflect the local populations. With the advent of expanded newborn screening relatively benign forms of fatty acid oxidation disorders have been commonly encountered. This high prevalence may reflect a selective evolutionary advantage as similar conditions have been found in other ethnic groups with traditionally high fat and low carbohydrate diets. HLA haplotypes of indigenous populations are less represented in international stem cell transplant databanks thereby making the option of human stem cell transplant more challenging. The recent discovery that short-chain enoyl-CoA hydratase deficiency is particularly common in New Zealand with nearly a dozen cases identified this year suggests there is still a lot to learn regarding Māori and Pacific and indeed an indigenous metabolic disease.
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Affiliation(s)
- Callum Wilson
- National Metabolic Service, Auckland City Hospital and Starship Children's Hospital, Auckland, New Zealand
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Bernhardt I, Glamuzina E, Dowsett LK, Webster D, Knoll D, Carpenter K, Bennett MJ, Maeda M, Wilson C. Genotype–phenotype correlations in
CPT1A
deficiency detected by newborn screening in Pacific populations. JIMD Rep 2022; 63:322-329. [PMID: 35822099 PMCID: PMC9259392 DOI: 10.1002/jmd2.12271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/04/2022] [Accepted: 01/10/2022] [Indexed: 11/30/2022] Open
Abstract
Carnitine palmitoyltransferase 1A (CPT1A) deficiency is a long chain fatty acid oxidation disorder, typically presenting with hypoketotic hypoglycaemia and liver dysfunction during fasting and intercurrent illness. Classical CPT1A deficiency is a rare disease, although a milder ‘Arctic variant' (p.P479L) is common in the Inuit population. Since the introduction of expanded metabolic screening (EMS), the newborn screening programmes of Hawai'i and New Zealand (NZ) have detected a significant increase in the incidence of CPT1A deficiency. We report 22 individuals of Micronesian descent (12 in NZ and 10 in Hawai'i), homozygous for a CPT1A c.100T>C (p.S34P) variant detected by EMS or ascertained following diagnosis of a family member. No individuals with the Micronesian variant presented clinically with metabolic decompensation prior to diagnosis or during follow‐up. Three asymptomatic homozygous adults were detected following the diagnosis of their children by EMS. CPT1A activity in cultured skin fibroblasts showed residual enzyme activity of 26% of normal controls. Secondly, we report three individuals from two unrelated Niuean families who presented clinically with symptoms of classic CPT1A deficiency, prior to the introduction of EMS. All were found to be homozygous for a CPT1A c.2122A>C (p.S708R) variant. CPT1A activity in fibroblasts of all three individuals was severely reduced at 4% of normal controls. Migration pressure, in part due to climate change may lead to increased frequency of presentation of Pacific peoples to regional metabolic services around the world. Knowledge of genotype–phenotype correlations in these populations will therefore inform counselling and treatment of those detected by newborn screening.
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Affiliation(s)
- Isaac Bernhardt
- National Metabolic Service Auckland City Hospital and Starship Children's Hospital Auckland New Zealand
| | - Emma Glamuzina
- National Metabolic Service Auckland City Hospital and Starship Children's Hospital Auckland New Zealand
| | - Leah K. Dowsett
- Department of Pediatrics University of Hawai'i John A. Burns School of Medicine Honolulu Hawai'i USA
- Hawai'i Community Genetics Honolulu Hawai'i USA
| | - Dianne Webster
- Newborn Metabolic Screening Unit Auckland City Hospital Auckland New Zealand
| | - Detlef Knoll
- Chemical Pathology (Section New Born Screening) Auckland City Hospital Auckland New Zealand
| | | | - Michael J. Bennett
- Perelman School of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
| | - Michelle Maeda
- Hawai'i Community Genetics Honolulu Hawai'i USA
- State of Hawai'i Department of Health Children with Special Health Needs Program Honolulu Hawai'i USA
| | - Callum Wilson
- National Metabolic Service Auckland City Hospital and Starship Children's Hospital Auckland New Zealand
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8
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Malyarchuk BA, Derenko MV, Denisova GA. Adaptive Changes in Fatty Acid Desaturation Genes in Indigenous Populations of Northeast Siberia. RUSS J GENET+ 2021. [DOI: 10.1134/s1022795421120103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Laubach K, Zhang J, Chen X. The p53 Family: A Role in Lipid and Iron Metabolism. Front Cell Dev Biol 2021; 9:715974. [PMID: 34395447 PMCID: PMC8358664 DOI: 10.3389/fcell.2021.715974] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/08/2021] [Indexed: 12/11/2022] Open
Abstract
The p53 family of tumor suppressors, which includes p53, p63, and p73, has a critical role in many biological processes, such as cell cycle arrest, apoptosis, and differentiation. In addition to tumor suppression, the p53 family proteins also participate in development, multiciliogenesis, and fertility, indicating these proteins have diverse roles. In this review, we strive to cover the relevant studies that demonstrate the roles of p53, p63, and p73 in lipid and iron metabolism.
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Affiliation(s)
| | | | - Xinbin Chen
- Comparative Oncology Laboratory, Schools of Veterinary Medicine and Medicine, University of California, Davis, Davis, CA, United States
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Marsden D, Bedrosian CL, Vockley J. Impact of newborn screening on the reported incidence and clinical outcomes associated with medium- and long-chain fatty acid oxidation disorders. Genet Med 2021; 23:816-829. [PMID: 33495527 PMCID: PMC8105167 DOI: 10.1038/s41436-020-01070-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 02/07/2023] Open
Abstract
Fatty acid oxidation disorders (FAODs) are potentially fatal inherited disorders for which management focuses on early disease detection and dietary intervention to reduce the impact of metabolic crises and associated spectrum of clinical symptoms. They can be divided functionally into long-chain (LC-FAODs) and medium-chain disorders (almost exclusively deficiency of medium-chain acyl-coenzyme A dehydrogenase). Newborn screening (NBS) allows prompt identification and management. FAOD detection rates have increased following the addition of FAODs to NBS programs in the United States and many developed countries. NBS-identified neonates with FAODs may remain asymptomatic with dietary management. Evidence from numerous studies suggests that NBS-identified patients have improved outcomes compared with clinically diagnosed patients, including reduced rates of symptomatic manifestations, neurodevelopmental impairment, and death. The limitations of NBS include the potential for false-negative and false-positive results, and the need for confirmatory testing. Although NBS alone does not predict the consequences of disease, outcomes, or management needs, subsequent genetic analyses may have predictive value. Genotyping can provide valuable information on the nature and frequency of pathogenic variants involved with FAODs and their association with specific phenotypes. Long-term follow-up to fully understand the clinical spectrum of NBS-identified patients and the effect of different management strategies is needed.
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Affiliation(s)
| | | | - Jerry Vockley
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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11
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Malyarchuk BA. [Genetic markers on the distribution of ancient marine hunters in Priokhotye]. Vavilovskii Zhurnal Genet Selektsii 2021; 24:539-544. [PMID: 33659839 PMCID: PMC7716533 DOI: 10.18699/vj20.646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Представлен обзор сведений о генетическом полиморфизме современного и древнего населения
Севера Азии и Америки с целью реконструкции истории миграций древних морских охотников в Охотоморском
регионе. Проанализированы данные о полиморфизме митохондриальной ДНК и распространенности «арктиче-
ской» мутации – варианта rs80356779-A гена CPT1A. Известно, что «арктический» вариант гена CPT1A с высокой
частотой распространен в современных популяциях эскимосов, чукчей, коряков и других народов Охотоморско-
го региона, хозяйственный уклад которых связан с морским зверобойным промыслом. Согласно палеогеномным
данным, самые ранние находки «арктического» варианта гена CPT1A обнаружены у гренландских и канадских па-
леоэскимосов (4 тыс. лет назад), представителей токаревской культуры Северного Приохотья (3 тыс. лет назад) и
носителей культуры позднего дзёмона острова Хоккайдо (3.5–3.8 тыс. лет назад). Результаты анализа позволили
выявить несколько миграционных событий, связанных с распространением морских охотников в Охотоморском
регионе. Самая поздняя миграция, оставившая следы у носителей культуры эпи-дзёмон (2.0–2.5 тыс. лет назад),
привнесла с севера Приохотья на Хоккайдо и соседние территории Приамурья митохондриальную гаплогруппу
G1b и «арктический» вариант гена CPT1A. Следы более ранней миграции, также привнесшей «арктическую» мута-
цию, зарегистрированы у населения позднего дзёмона Хоккайдо (3.5–3.8 тыс. лет назад). Проведен филогенети-
ческий анализ митохондриальных геномов, относящихся к редкой гаплогруппе C1a, встречающейся у населения
Дальнего Востока и Японии, но в филогенетическом отношении родственной C1-гаплогруппам американских
индейцев. Результаты показали, что дивергенция митохондриальных линий в пределах гаплогруппы C1a проис-
ходила в диапазоне от 7.9 до 6.6 тыс. лет назад, а возраст японской ветви гаплогруппы C1a составляет ~5.2 тыс.
лет. Пока неизвестно, связана ли эта миграция с распространением «арктического» варианта гена CPT1A или же
присутствие C1a-гаплотипов у населения островов Японии маркирует собой еще один, более ранний, эпизод
миграционной истории, связывающей население северо-западной Пацифики и Северной Америки.
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Affiliation(s)
- B A Malyarchuk
- Institute of Biological Problems of the North of the Far-East Branch of the Russian Academy of Sciences, Magadan, Russia
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Collins SA, Edmunds S, Akearok GH, Thompson JR, Erickson AC, Hildes-Ripstein E, Miners A, Somerville M, Goldfarb DM, Rockman-Greenberg C, Arbour L. Association of the CPT1A p.P479L Metabolic Gene Variant With Childhood Respiratory and Other Infectious Illness in Nunavut. Front Pediatr 2021; 9:678553. [PMID: 34295859 PMCID: PMC8290072 DOI: 10.3389/fped.2021.678553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/14/2021] [Indexed: 11/24/2022] Open
Abstract
Objective: Infectious illness, including lower respiratory tract infection (LRTI), is a leading cause of childhood morbidity and infant mortality in Inuit children in Nunavut Canada. The carnitine palmitoyltransferase 1A (CPT1A) p.P479L variant is common in arctic Indigenous populations of Alaska, Canada, and Greenland. CPT1A is a fatty acid oxidation enzyme expressed in the liver, immunocytes and other tissues, and is needed to use fats for energy during fasting. Previous association of the variant with early childhood infectious illness and infant death has been challenged because of sample size and limited adjustment for confounders. We evaluated whether the p.P479L variant is associated with infectious illness in Inuit children of Nunavut, Canada. Methods: We conducted a retrospective clinical chart review of 2,225 Inuit children (0-5 years) for infectious illness (including otitis media, gastroenteritis, and hospital admission for LRTI), prenatal, perinatal, and socioeconomic indicators, subsequently linking to CPT1A genotype. Multivariable logistic regression adjusted for birth characteristics, breastfeeding, maternal smoking, food insecurity, and socioeconomic indicators. Results: Overall, 27% of children were hospitalized for LRTI, 86% had otitis media and 50% had gastroenteritis. The p.P479L allele frequency was 0.82. In multivariable analysis, p.P479L homozygosity was associated with LRTI admission (aOR:2.88 95%CI:1.46-5.64), otitis media (aOR:1.83, 95%CI:1.05-3.21), and gastroenteritis (aOR:1.74, 95%CI:1.09-2.77), compared to non-carriers. Conclusion: Children homozygous for the p.P479L variant were more likely to experience infectious illness than non-carriers, including hospitalization for respiratory tract infections. Given the role of CPT1A in immunocytes, our findings indicate that more study is needed to determine if there is a role of the variant in immune response. Continued Inuit involvement is essential when considering next steps.
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Affiliation(s)
- Sorcha A Collins
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Sharon Edmunds
- Department of Research, Monitoring, and Evaluation, Nunavut Tunngavik Inc., Iqaluit, NU, Canada
| | | | | | - Anders C Erickson
- School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada
| | - Elske Hildes-Ripstein
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada
| | - Amber Miners
- Department of Health, Government of Nunavut, Iqaluit, NU, Canada
| | - Martin Somerville
- Department of Laboratory Medicine and Pathobiology University of Toronto, Toronto, ON, Canada
| | - David M Goldfarb
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | | | - Laura Arbour
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
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13
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Aronica L, Volek J, Poff A, D'agostino DP. Genetic variants for personalised management of very low carbohydrate ketogenic diets. BMJ Nutr Prev Health 2020; 3:363-373. [PMID: 33521546 PMCID: PMC7841814 DOI: 10.1136/bmjnph-2020-000167] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/04/2020] [Accepted: 11/15/2020] [Indexed: 01/07/2023] Open
Abstract
The ketogenic diet (KD) is a low-carbohydrate, high-fat, adequate-protein diet proven to be effective for the reversal of obesity, metabolic syndrome and type 2 diabetes, and holding therapeutic potential for the prevention and treatment of other chronic diseases. Genetic and dynamic markers of KD response may help to identify individuals most likely to benefit from KD and point to individuals at higher risk for adverse health outcomes. Here, we provide a clinician-friendly review of state-of-the-art research on biomarkers of KD response for a variety of outcomes including weight loss, body composition and cognitive performance drawing data from both intervention trials and case reports of rare inborn errors of metabolism. We also present a selection of the most promising candidate genes to evaluate in future studies and discuss key aspects of study design and variant interpretation that may help accelerate the implementation of these biomarkers in clinical practice.
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Affiliation(s)
- Lucia Aronica
- Nutrition Science, Metagenics Inc, Gig Harbor, Washington, USA.,Medicine, Stanford University, Stanford, California, USA
| | - Jeff Volek
- Human Sciences, The Ohio State University, Columbus, Ohio, USA
| | - Angela Poff
- Medicine Molecular Pharmacology & Physiology, University of South Florida, Tampa, Florida, USA
| | - Dominic P D'agostino
- Medicine Molecular Pharmacology & Physiology, University of South Florida, Tampa, Florida, USA
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Werren EA, Garcia O, Bigham AW. Identifying adaptive alleles in the human genome: from selection mapping to functional validation. Hum Genet 2020; 140:241-276. [PMID: 32728809 DOI: 10.1007/s00439-020-02206-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 07/07/2020] [Indexed: 12/19/2022]
Abstract
The suite of phenotypic diversity across geographically distributed human populations is the outcome of genetic drift, gene flow, and natural selection throughout human evolution. Human genetic variation underlying local biological adaptations to selective pressures is incompletely characterized. With the emergence of population genetics modeling of large-scale genomic data derived from diverse populations, scientists are able to map signatures of natural selection in the genome in a process known as selection mapping. Inferred selection signals further can be used to identify candidate functional alleles that underlie putative adaptive phenotypes. Phenotypic association, fine mapping, and functional experiments facilitate the identification of candidate adaptive alleles. Functional investigation of candidate adaptive variation using novel techniques in molecular biology is slowly beginning to unravel how selection signals translate to changes in biology that underlie the phenotypic spectrum of our species. In addition to informing evolutionary hypotheses of adaptation, the discovery and functional annotation of adaptive alleles also may be of clinical significance. While selection mapping efforts in non-European populations are growing, there remains a stark under-representation of diverse human populations in current public genomic databases, of both clinical and non-clinical cohorts. This lack of inclusion limits the study of human biological variation. Identifying and functionally validating candidate adaptive alleles in more global populations is necessary for understanding basic human biology and human disease.
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Affiliation(s)
- Elizabeth A Werren
- Department of Human Genetics, The University of Michigan, Ann Arbor, MI, USA
- Department of Anthropology, The University of Michigan, Ann Arbor, MI, USA
| | - Obed Garcia
- Department of Anthropology, The University of Michigan, Ann Arbor, MI, USA
| | - Abigail W Bigham
- Department of Anthropology, University of California Los Angeles, 341 Haines Hall, Los Angeles, CA, 90095, USA.
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15
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Mørkholt AS, Oklinski MK, Larsen A, Bockermann R, Issazadeh-Navikas S, Nieland JGK, Kwon TH, Corthals A, Nielsen S, Nieland JDV. Pharmacological inhibition of carnitine palmitoyl transferase 1 inhibits and reverses experimental autoimmune encephalitis in rodents. PLoS One 2020; 15:e0234493. [PMID: 32520953 PMCID: PMC7286491 DOI: 10.1371/journal.pone.0234493] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 05/26/2020] [Indexed: 02/01/2023] Open
Abstract
Multiple sclerosis (MS) is a neurodegenerative disease characterized by demyelination and inflammation. Dysregulated lipid metabolism and mitochondrial dysfunction are hypothesized to play a key role in MS. Carnitine Palmitoyl Transferase 1 (CPT1) is a rate-limiting enzyme for beta-oxidation of fatty acids in mitochondria. The therapeutic effect of pharmacological CPT1 inhibition with etomoxir was investigated in rodent models of myelin oligodendrocyte glycoprotein- and myelin basic protein-induced experimental autoimmune encephalitis (EAE). Mice receiving etomoxir showed lower clinical score compared to placebo, however this was not significant. Rats receiving etomoxir revealed significantly lower clinical score and lower body weight compared to placebo group. When comparing etomoxir with interferon-β (IFN-β), IFN-β had no significant therapeutic effects, whereas etomoxir treatment starting at day 1 and 5 significantly improved the clinical scores compared to the IFN-β and the placebo group. Immunohistochemistry and image assessments of brain sections from rats with EAE showed higher myelination intensity and decreased expression of CPT1A in etomoxir-treated rats compared to placebo group. Moreover, etomoxir mediated increased interleukin-4 production and decreased interleukin-17α production in activated T cells. In conclusion, CPT1 is a key protein in the pathogenesis of EAE and MS and a crucial therapeutic target for the treatment.
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Affiliation(s)
| | | | - Agnete Larsen
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Robert Bockermann
- Biotech Research and Innovation Centre, Copenhagen University, Copenhagen N, Denmark
| | | | | | - Tae-Hwan Kwon
- Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu, Korea
| | - Angelique Corthals
- Department of Science, John Jay College of Criminal Justice, City University of New York, New York, New York, United States of America
| | - Søren Nielsen
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.,Meta-IQ, ApS, Aarhus C, Denmark
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16
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Collins SA, Hildes-Ripstein GE, Thompson JR, Edmunds S, Miners A, Rockman-Greenberg C, Arbour L. Neonatal hypoglycemia and the CPT1A P479L variant in term newborns: A retrospective cohort study of Inuit newborns from Kivalliq Nunavut. Paediatr Child Health 2020; 26:218-227. [PMID: 34131458 DOI: 10.1093/pch/pxaa039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/12/2020] [Indexed: 11/14/2022] Open
Abstract
Introduction Neonatal hypoglycemia (NH) in the first days of life can largely be prevented by recognizing those at risk and managing accordingly. The CPT1A P479L variant is prevalent in northern Indigenous populations and is a possible risk factor for hypoglycemia. We report on NH incidence in the Kivalliq region of Nunavut, where all Inuit newborns are screened for NH. Methods We reviewed clinical charts of 728 Inuit newborns from Kivalliq (January 1, 2010 to December 31, 2013) for blood glucose (BG) levels and infant/maternal characteristics, linking to CPT1A genotype; 616 newborns had BG data from 2 to 48 hours of life. NH was defined using Canadian Paediatric Society guidelines (≤2.0 mmol/L at 2 hours, <2.6 mmol/L at 2 to 48 hours). Results NH was documented in 21.4% overall, 24.4% of at-risk newborns and 19.5% of term newborns with no risk factors (≥37 weeks gestation, term-NRF). NH was documented in 22.0% of CPT1A P479L homozygous, 19.8% of P479L heterozygous and 4.8% of noncarrier term-NRF newborns. With multivariable logistic regression, the adjusted ORs for developing NH in term-NRF newborns was 4.97 for CPT1A P479L homozygotes (95% confidence interval [CI]:0.65-38.35, P=0.19) and 4.71 for P479L heterozygotes (95% CI:0.57-37.89, P=0.15). Conclusion Term-NRF newborns had a higher NH incidence than previously reported, similar to that for at-risk newborns, possibly due to the CPT1A P479L variant. Since only Inuit newborns from Kivalliq are screened for NH, further study of long-term outcomes of NH in this population and the role of the P479L variant are warranted to determine if neonatal BG screening is indicated in all Inuit newborns.
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Affiliation(s)
- Sorcha A Collins
- Department of Medical Genetics, University of British Columbia, Victoria, British Columbia
| | | | | | - Sharon Edmunds
- Department of Social and Cultural Development, Nunavut Tunngavik Inc., Iqaluit, Nunavut
| | - Amber Miners
- Department of Health, Government of Nunavut, Iqaluit, Nunavut
| | | | - Laura Arbour
- Department of Medical Genetics, University of British Columbia, Victoria, British Columbia
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17
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Hale N. Inuit metabolism revisited: what drove the selective sweep of CPT1a L479? Mol Genet Metab 2020; 129:255-271. [PMID: 32088118 DOI: 10.1016/j.ymgme.2020.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 01/30/2020] [Indexed: 12/31/2022]
Abstract
This article reassesses historical studies of Inuit metabolism in light of recent developments in evolutionary genetics. It discusses the possible selective advantage of a variant of CPT1a, which encodes the rate limiting enzyme in hepatic fatty acid oxidation. The L479 variant of CPT1a underwent one of the strongest known selective sweeps in human history and is specific to Inuit and Yu'pik populations. Recent hypotheses predict that this variant may have been selected in response to possible detrimental effects of chronic ketosis in communities with very low carbohydrate consumption. Assessing these hypotheses alongside several alternative explanations of the selective sweep, this article challenges the notion that the selection of L479 is linked to predicted detrimental effects of ketosis. Bringing together for the first time data from biochemical, metabolic, and physiological studies inside and outside the Inuit sphere, it aims to provide a broader interpretative framework and a more comprehensive way to understand the selective sweep. It suggests that L479 may have provided a selective advantage in glucose conservation as part of a metabolic adaptation to very low carbohydrate and high protein consumption, but not necessarily a ketogenic state, in an extremely cold environment. A high intake of n-3 fatty acids may be linked to selection through the mitigation of a detrimental effect of the mutation that arises in the fasted state. The implications of these conclusions for our broader understanding of very low carbohydrate metabolism, and for dietary recommendations for Inuit and non-Inuit populations, are discussed.
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18
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Abstract
The purpose of the present review is to describe how human physiology at very low carbohydrate intakes relates to the criteria for nutritional essentiality. Although we did not limit ourselves to one particular type or function of carbohydrates, we did primarily focus on glucose utilisation as that function was used to determine the recommended daily allowance. In the general population, the human body is able to endogenously synthesise carbohydrates, and does not show signs of deficiency in the absence of dietary carbohydrates. However, in certain genetic defects, such as glycogen storage disease type I, absence of dietary carbohydrates causes abnormalities that are resolved with dietary supplementation of carbohydrates. Therefore, dietary carbohydrates may be defined as conditionally essential nutrients because they are nutrients that are not required in the diet for the general population but are required for specific subpopulations. Ketosis may be considered a physiological normal state due to its occurrence in infants in addition to at very low carbohydrate intakes. Although sources of dietary carbohydrates can provide beneficial micronutrients, no signs of micronutrient deficiencies have been reported in clinical trials of low-carbohydrate ketogenic diets. Nonetheless, more research is needed on how micronutrient requirements can change depending on the dietary and metabolic context. More research is also needed on the role of dietary fibre during a low-carbohydrate ketogenic diet as the beneficial effects of dietary fibre were determined on a standard diet and several studies have shown beneficial effects of decreasing non-digestible carbohydrates.
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19
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Schlaepfer IR, Joshi M. CPT1A-mediated Fat Oxidation, Mechanisms, and Therapeutic Potential. Endocrinology 2020; 161:5695911. [PMID: 31900483 DOI: 10.1210/endocr/bqz046] [Citation(s) in RCA: 282] [Impact Index Per Article: 70.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/31/2019] [Indexed: 12/15/2022]
Abstract
Energy homeostasis during fasting or prolonged exercise depends on mitochondrial fatty acid oxidation (FAO). This pathway is crucial in many tissues with high energy demand and its disruption results in inborn FAO deficiencies. More than 15 FAO genetic defects have been currently described, and pathological variants described in circumpolar populations provide insights into its critical role in metabolism. The use of fatty acids as energy requires more than 2 dozen enzymes and transport proteins, which are involved in the activation and transport of fatty acids into the mitochondria. As the key rate-limiting enzyme of FAO, carnitine palmitoyltransferase I (CPT1) regulates FAO and facilitates adaptation to the environment, both in health and in disease, including cancer. The CPT1 family of proteins contains 3 isoforms: CPT1A, CPT1B, and CPT1C. This review focuses on CPT1A, the liver isoform that catalyzes the rate-limiting step of converting acyl-coenzyme As into acyl-carnitines, which can then cross membranes to get into the mitochondria. The regulation of CPT1A is complex and has several layers that involve genetic, epigenetic, physiological, and nutritional modulators. It is ubiquitously expressed in the body and associated with dire consequences linked with genetic mutations, metabolic disorders, and cancers. This makes CPT1A an attractive target for therapeutic interventions. This review discusses our current understanding of CPT1A expression, its role in heath and disease, and the potential for therapeutic opportunities targeting this enzyme.
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Affiliation(s)
- Isabel R Schlaepfer
- University of Colorado School of Medicine, Division of Medical Oncology, Aurora
| | - Molishree Joshi
- University of Colorado School of Medicine, Department of Pharmacology, Aurora, Colorado
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20
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Briant LJB, Dodd MS, Chibalina MV, Rorsman NJG, Johnson PRV, Carmeliet P, Rorsman P, Knudsen JG. CPT1a-Dependent Long-Chain Fatty Acid Oxidation Contributes to Maintaining Glucagon Secretion from Pancreatic Islets. Cell Rep 2019; 23:3300-3311. [PMID: 29898400 PMCID: PMC6581793 DOI: 10.1016/j.celrep.2018.05.035] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/19/2018] [Accepted: 05/11/2018] [Indexed: 12/30/2022] Open
Abstract
Glucagon, the principal hyperglycemic hormone, is secreted from pancreatic islet α cells as part of the counter-regulatory response to hypoglycemia. Hence, secretory output from α cells is under high demand in conditions of low glucose supply. Many tissues oxidize fat as an alternate energy substrate. Here, we show that glucagon secretion in low glucose conditions is maintained by fatty acid metabolism in both mouse and human islets, and that inhibiting this metabolic pathway profoundly decreases glucagon output by depolarizing α cell membrane potential and decreasing action potential amplitude. We demonstrate, by using experimental and computational approaches, that this is not mediated by the KATP channel, but instead due to reduced operation of the Na+-K+ pump. These data suggest that counter-regulatory secretion of glucagon is driven by fatty acid metabolism, and that the Na+-K+ pump is an important ATP-dependent regulator of α cell function. Glucagon secretion in low glucose is maintained by CPT1a-dependent FAO Loss of CPT1a-dependent FAO in mouse and human islets decreases glucagon secretion CPT1a-dependent FAO maintains glucagon secretion by supplying ATP to the Na+-K+-ATPase CPT1a-dependent FAO contributes to the counter-regulatory secretion of glucagon
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Affiliation(s)
- Linford J B Briant
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK; Department of Computer Science, University of Oxford, Oxford OX1 3QD, UK
| | - Michael S Dodd
- Department of Physiology, Anatomy & Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK; Faculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, UK
| | - Margarita V Chibalina
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK
| | - Nils J G Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK
| | - Paul R V Johnson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK; Oxford National Institute for Health Research, Biomedical Research Centre, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, VIB-KU Leuven Center for Cancer Biology, Leuven, Belgium
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK; Metabolic Research, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Göteborg, Box 433, 405 30 Göteborg, Sweden
| | - Jakob G Knudsen
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LE, UK.
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21
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Mørkholt AS, Trabjerg MS, Oklinski MKE, Bolther L, Kroese LJ, Pritchard CEJ, Huijbers IJ, Nieland JDV. CPT1A plays a key role in the development and treatment of multiple sclerosis and experimental autoimmune encephalomyelitis. Sci Rep 2019; 9:13299. [PMID: 31527712 PMCID: PMC6746708 DOI: 10.1038/s41598-019-49868-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/27/2019] [Indexed: 01/10/2023] Open
Abstract
Human mutations in carnitine palmitoyl transferase 1A (CPT1A) are correlated with a remarkably low prevalence of multiple sclerosis (MS) in Inuits (P479L) and Hutterites (G710E). To elucidate the role of CPT1A, we established a Cpt1a P479L mouse strain and evaluated its sensitivity to experimental autoimmune encephalomyelitis (EAE) induction. Since CPT1a is a key molecule in lipid metabolism, we compared the effects of a high-fat diet (HFD) and normal diet (ND) on disease progression. The disease severity increased significantly in WT mice compared to that in Cpt1 P479L mice. In addition, WT mice receiving HFD showed markedly exacerbated disease course when compared either with Cpt1a P479L mice receiving HFD or WT control group receiving ND. Induction of EAE caused a significant decrease of myelin basic protein expression in the hindbrain of disease affected WT mice in comparison to Cpt1a P479L mice. Further, WT mice showed increased expression of oxidative stress markers like Nox2 and Ho-1, whereas expression of mitochondrial antioxidants regulator Pgc1α was increased in Cpt1a P479L mice. Our results suggest that, lipids metabolism play an important role in EAE, as shown by the higher severity of disease progression in both WT EAE and WT EAF HFD-fed mice in contrast to their counterpart Cpt1a P479L mutant mice. Interestingly, mice with downregulated lipid metabolism due to the Cpt1a P479L mutation showed resistance to EAE induction. These findings support a key role for CPT1A in the development of EAE and could be a promising target in MS treatment.
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Affiliation(s)
- Anne Skøttrup Mørkholt
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7, 9220, Aalborg, Denmark
| | - Michael Sloth Trabjerg
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7, 9220, Aalborg, Denmark
| | | | - Luise Bolther
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7, 9220, Aalborg, Denmark
| | - Lona John Kroese
- Mouse Clinic for Cancer and Aging Research, Transgenic Facility, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
| | - Colin Eliot Jason Pritchard
- Mouse Clinic for Cancer and Aging Research, Transgenic Facility, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
| | - Ivo Johan Huijbers
- Mouse Clinic for Cancer and Aging Research, Transgenic Facility, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
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22
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Szpak M, Xue Y, Ayub Q, Tyler‐Smith C. How well do we understand the basis of classic selective sweeps in humans? FEBS Lett 2019; 593:1431-1448. [DOI: 10.1002/1873-3468.13447] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/29/2019] [Accepted: 05/17/2019] [Indexed: 12/14/2022]
Affiliation(s)
| | - Yali Xue
- The Wellcome Sanger Institute Hinxton UK
| | - Qasim Ayub
- School of Science Monash University Malaysia Bandar Sunway Malaysia
- Tropical Medicine and Biology Multidisciplinary Platform Monash University Malaysia Genomics Facility Bandar Sunway Malaysia
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23
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Barroso I, McCarthy MI. The Genetic Basis of Metabolic Disease. Cell 2019; 177:146-161. [PMID: 30901536 PMCID: PMC6432945 DOI: 10.1016/j.cell.2019.02.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/11/2019] [Accepted: 02/14/2019] [Indexed: 02/06/2023]
Abstract
Recent developments in genetics and genomics are providing a detailed and systematic characterization of the genetic underpinnings of common metabolic diseases and traits, highlighting the inherent complexity within systems for homeostatic control and the many ways in which that control can fail. The genetic architecture underlying these common metabolic phenotypes is complex, with each trait influenced by hundreds of loci spanning a range of allele frequencies and effect sizes. Here, we review the growing appreciation of this complexity and how this has fostered the implementation of genome-scale approaches that deliver robust mechanistic inference and unveil new strategies for translational exploitation.
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Affiliation(s)
- Inês Barroso
- Wellcome Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.
| | - Mark I McCarthy
- Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK; Oxford Centre for Diabetes, Endocrinology, and Metabolism, University of Oxford, Churchill Hospital, Old Road, Headington, Oxford OX3 7LJ, UK; Oxford NIHR Biomedical Research Centre, Churchill Hospital, Old Road, Headington, Oxford OX3 7LJ, UK
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24
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KANZAWA-KIRIYAMA HIDEAKI, JINAM TIMOTHYA, KAWAI YOSUKE, SATO TAKEHIRO, HOSOMICHI KAZUYOSHI, TAJIMA ATSUSHI, ADACHI NOBORU, MATSUMURA HIROFUMI, KRYUKOV KIRILL, SAITOU NARUYA, SHINODA KENICHI. Late Jomon male and female genome sequences from the Funadomari site in Hokkaido, Japan. ANTHROPOL SCI 2019. [DOI: 10.1537/ase.190415] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
| | - TIMOTHY A. JINAM
- Division of Population Genetics, National Institute of Genetics, Mishima
| | - YOSUKE KAWAI
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo
| | - TAKEHIRO SATO
- Department of Bioinformatics and Genomics, Graduate School of Medical Sciences, Kanazawa University, Kanazawa
| | - KAZUYOSHI HOSOMICHI
- Department of Bioinformatics and Genomics, Graduate School of Medical Sciences, Kanazawa University, Kanazawa
| | - ATSUSHI TAJIMA
- Department of Bioinformatics and Genomics, Graduate School of Medical Sciences, Kanazawa University, Kanazawa
| | - NOBORU ADACHI
- Department of Legal Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo
| | - HIROFUMI MATSUMURA
- Second Division of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo
| | - KIRILL KRYUKOV
- Department of Molecular Life Science, School of Medicine, Tokai University, Isehara
| | - NARUYA SAITOU
- Division of Population Genetics, National Institute of Genetics, Mishima
| | - KEN-ICHI SHINODA
- Department of Anthropology, National Museum of Nature and Science, Tsukuba
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25
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Andersen MK, Hansen T. Genetics of metabolic traits in Greenlanders: lessons from an isolated population. J Intern Med 2018; 284:464-477. [PMID: 30101502 DOI: 10.1111/joim.12814] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In this review, we describe the extraordinary population of Greenland, which differs from large outbred populations of Europe and Asia, both in terms of population history and living conditions. Many years in isolation, small population size and an extreme environment have shaped the genetic composition of the Greenlandic population. The unique genetic background combined with the transition from a traditional Inuit lifestyle and diet, to a more Westernized lifestyle, has led to an increase in the prevalence of metabolic conditions like obesity, where the prevalence from 1993 to 2010 has increased from 16.4% to 19.4% among men, and from 13.0% to 25.4% among women, type 2 diabetes and cardiovascular diseases. The genetic susceptibility to metabolic conditions has been explored in Greenlanders, as well as other isolated populations, taking advantage of population-genetic properties of these populations. During the last 10 years, these studies have provided examples of loci showing evidence of positive selection, due to adaption to Arctic climate and Inuit diet, including TBC1D4 and FADS/CPT1A, and have facilitated the discovery of several loci associated with metabolic phenotypes. Most recently, the c.2433-1G>A loss-of-function variant in ADCY3 associated with obesity and type 2 diabetes was described. This locus has provided novel biological insights, as it has been shown that reduced ADCY3 function causes obesity through disrupted function in primary cilia. Future studies of isolated populations will likely provide further genetic as well as biological insights.
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Affiliation(s)
- M K Andersen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - T Hansen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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26
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Sinclair G, Collins S, Arbour L, Vallance H. The p.P479L variant in CPT1A is associated with infectious disease in a BC First Nation. Paediatr Child Health 2018; 24:e111-e115. [PMID: 30996616 DOI: 10.1093/pch/pxy106] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Background The hepatic carnitine palmitoyltransferase I (CPT1A) p.P479L variant is common in Aboriginal populations across coastal British Columbia, Alaska, the Canadian North, and Greenland. While the high frequency of this variant suggests positive selection, other studies have shown an association with sudden unexpected death in infancy and infection. We utilized administrative health data to evaluate hospitalizations for a single year cohort of children of First Nations descent genotyped for the variant and, matched for location of birth. Seven years of data were reviewed for 150 children split evenly between CPT1A genotypes (homozyous, heterozygous, and noncarrier of the p.P479L variant). Results Children homozygous for the p.P479L allele had a higher rate of hospital admissions at 2.6 per individual as compared to noncarriers at 0.86. Heterozygous children also showed a significant increase at 1.9 per person. Length of stay per admission was increased for both p.P479L homozygotes and heterozygotes. The odds ratio (OR) for at least one hospitalization for any reason was increased for p.P479L homozygotes relative to noncarriers (OR=10.2, confidence interval [CI] 3.5 to 30.0) as were admissions for dental caries (OR=3.4, CI 1.5 to 7.8), acute lower respiratory tract infections (OR=6.0, CI 1.6 to 22.4), and otitis media (OR=13.5, CI 1.7 to 109.4). Conclusions The CPT1A p.P479L variant is associated with an increased rate of hospitalization for those homozygous, primarily for infectious disease causes. Heterozygotes also showed a small but significant increase in hospitalization rates suggesting some dosage effect. Functional studies will be required to identify the underlying pathological mechanism.
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Affiliation(s)
- Graham Sinclair
- Department of Pathology and Laboratory Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia
| | - Sorcha Collins
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia
| | - Laura Arbour
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia
| | - Hilary Vallance
- Department of Pathology and Laboratory Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia
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Skotte L, Koch A, Yakimov V, Zhou S, Søborg B, Andersson M, Michelsen SW, Navne JE, Mistry JM, Dion PA, Pedersen ML, Børresen ML, Rouleau GA, Geller F, Melbye M, Feenstra B. CPT1A Missense Mutation Associated With Fatty Acid Metabolism and Reduced Height in Greenlanders. ACTA ACUST UNITED AC 2018; 10:CIRCGENETICS.116.001618. [PMID: 28611031 DOI: 10.1161/circgenetics.116.001618] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 04/06/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Inuit have lived for thousands of years in an extremely cold environment on a diet dominated by marine-derived fat. To investigate how this selective pressure has affected the genetic regulation of fatty acid metabolism, we assessed 233 serum metabolic phenotypes in a population-based sample of 1570 Greenlanders. METHODS AND RESULTS Using array-based and targeted genotyping, we found that rs80356779, a p.Pro479Leu variant in CPT1A, was strongly associated with markers of n-3 fatty acid metabolism, including degree of unsaturation (P=1.16×10-34), levels of polyunsaturated fatty acids, n-3 fatty acids, and docosahexaoenic acid relative to total fatty acid levels (P=2.35×10-15, P=4.02×10-19, and P=7.92×10-27). The derived allele (L479) occurred at a frequency of 76.2% in our sample while being absent in most other populations, and we found strong signatures of positive selection at the locus. Furthermore, we found that each copy of L479 reduced height by an average of 2.1 cm (P=1.04×10-9). In exome sequencing data from a sister population, the Nunavik Inuit, we found no other likely causal candidate variant than rs80356779. CONCLUSION Our study shows that a common CPT1A missense mutation is strongly associated with a range of metabolic phenotypes and reduced height in Greenlanders. These findings are important from a public health perspective and highlight the usefulness of complex trait genetic studies in isolated populations.
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Affiliation(s)
- Line Skotte
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.).
| | - Anders Koch
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Victor Yakimov
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Sirui Zhou
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Bolette Søborg
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Mikael Andersson
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Sascha W Michelsen
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Johan E Navne
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Jacqueline M Mistry
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Patrick A Dion
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Michael L Pedersen
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Malene L Børresen
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Guy A Rouleau
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Frank Geller
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Mads Melbye
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.)
| | - Bjarke Feenstra
- From the Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark (L.S., A.K., V.Y., B.S., M.A., S.W.M., J.E.N., J.M.M., M.L.B., F.G., M.M., B.F.); Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada (S.Z., P.A.D., G.A.R.); Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada (P.A.D., G.A.R.); Département de Médecine, Faculté de Médecine, Université de Montréal, Quebec, Canada (S.Z.); Greenland Center for Health Research, Institute of Nursing and Health Science, University of Greenland, Nuuk, Greenland (M.L.P.); Department of Clinical Medicine, University of Copenhagen, Denmark (M.M.); and Department of Medicine, Stanford University School of Medicine, California (M.M.).
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Carnitine palmitoyltransferase 1A P479L and infant death: policy implications of emerging data. Genet Med 2017; 19:851-857. [PMID: 28125087 DOI: 10.1038/gim.2016.202] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 11/14/2016] [Indexed: 01/24/2023] Open
Abstract
Carnitine palmitoyltransferase 1 isoform A (CPT1A) is a crucial enzyme for the transport of long-chain fatty acids into the mitochondria. The CPT1A p.P479L variant is found in high frequencies among indigenous populations residing on the west and north coasts of Alaska and Canada and in northeast Siberia and Greenland. Epidemiological studies have reported a statistical association between P479L homozygosity and infant death in Alaska Native and Canadian Inuit populations. Here, we review the available evidence about the P479L variant and apply to these data the epidemiological criteria for assessing causal associations. We found insufficient evidence to support a causal association with infant death and, further, that if a causal association is present, then the genotype is likely to be only one of a complex set of factors contributing to an increased risk of infant death. We conclude that additional research is needed to clarify the observed association and to inform effective preventative measures for infant death. In light of these findings, we discuss the policy implications for public health efforts because policies based on the observed association between P479L homozygosity and infant death data are premature.Genet Med advance online publication 26 January 2017.
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Gessner BD, Wood T, Johnson MA, Richards CS, Koeller DM. Evidence for an association between infant mortality and homozygosity for the arctic variant of carnitine palmitoyltransferase 1A. Genet Med 2016; 18:933-9. [PMID: 26820065 PMCID: PMC4965343 DOI: 10.1038/gim.2015.197] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 11/17/2015] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Infant mortality in Alaska is highest among Alaska Native people from western/northern Alaska, a population with a high prevalence of a genetic variant (c.1436C>T; the arctic variant) of carnitine palmitoyltransferase 1A (CPT1A). METHODS We performed an unmatched case-control study to determine the relationship between the arctic variant and infant mortality. The cases were 110 Alaska Native infant deaths from 2006 to 2010 and the controls were 395 Alaska Native births from the same time period. In addition to the overall analysis, we conducted two subanalyses, one limited to subjects from western/northern Alaska and one limited to infants heterozygous or homozygous for the arctic variant. RESULTS Among western/northern Alaska residents, 66% of cases and 61% of controls were homozygous (adjusted odds ratio (aOR): 2.5; 95% confidence interval (CI): 1.3, 5.0). Among homozygous or heterozygous infants, 58% of cases and 44% of controls were homozygous (aOR: 2.3; 95% CI: 1.3, 4.0). Deaths associated with infection were more likely to be homozygous (OR: 2.9; 95% CI: 1.0-8.0). Homozygosity was strongly associated with a premorbid history of pneumonia, sepsis, or meningitis. CONCLUSION Homozygosity for the arctic variant is associated with increased risk of infant mortality, which may be mediated in part by an increase in infectious disease risk. Further studies are needed to determine whether the association we report represents a causal association between the CPT1A arctic variant and infectious disease-specific mortality.Genet Med 18 9, 933-939.
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Affiliation(s)
- Bradford D Gessner
- Alaska Division of Public Health, Anchorage, Alaska, USA
- Present address: EpiVac Consulting, Anchorage, Alaska, USA
| | - Thalia Wood
- Alaska Division of Public Health, Anchorage, Alaska, USA
- Present address: EpiVac Consulting, Anchorage, Alaska, USA
| | - Monique A Johnson
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon, USA
| | - Carolyn Sue Richards
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon, USA
| | - David M Koeller
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon, USA
- Department of Pediatrics, Oregon Health & Science University, Portland, Oregon, USA
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Bankoff RJ, Perry GH. Hunter-gatherer genomics: evolutionary insights and ethical considerations. Curr Opin Genet Dev 2016; 41:1-7. [PMID: 27400119 DOI: 10.1016/j.gde.2016.06.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 10/21/2022]
Abstract
Hunting and gathering societies currently comprise only a small proportion of all human populations. However, the geographic and environmental diversity of modern hunter-gatherer groups, their inherent dependence on ecological resources, and their connection to patterns of behavior and subsistence that represent the vast majority of human history provide opportunities for scientific research to deliver major insights into the evolutionary history of our species. We review recent evolutionary genomic studies of hunter-gatherers, focusing especially on those that identify and functionally characterize phenotypic adaptations to local environments. We also call attention to specific ethical issues that scientists conducting hunter-gatherer genomics research ought to consider, including potential social and economic tensions between traditionally mobile hunter-gatherers and the land ownership-based nation-states by which they are governed, and the implications of genomic-based evidence of long-term evolutionary associations with particular habitats.
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Affiliation(s)
- Richard J Bankoff
- Department of Anthropology, Pennsylvania State University, University Park, PA 16802, USA; Intercollege Program in Bioethics, Pennsylvania State University, University Park, PA 16802, USA.
| | - George H Perry
- Department of Anthropology, Pennsylvania State University, University Park, PA 16802, USA; Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
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Tereshchenko SY, Smolnikova MV. A pilot study of inherited carnitine palmitoyltransferase deficiency as an ethnogenetic risk factor of infant mortality in indigenous populations of the Far North. HUMAN PHYSIOLOGY 2016. [DOI: 10.1134/s0362119716020158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Choi JS, Yoo HW, Lee KJ, Ko JM, Moon JS, Ko JS. Novel Mutations in the CPT1A Gene Identified in the Patient Presenting Jaundice as the First Manifestation of Carnitine Palmitoyltransferase 1A Deficiency. Pediatr Gastroenterol Hepatol Nutr 2016; 19:76-81. [PMID: 27066452 PMCID: PMC4821986 DOI: 10.5223/pghn.2016.19.1.76] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/14/2015] [Accepted: 10/04/2015] [Indexed: 11/22/2022] Open
Abstract
Carnitine palmitoyltransferase 1A (CPT1A) is an enzyme functioning in mitochondrial fatty acid oxidation (FAO) of the liver. Patients with CPT1A deficiency have impaired mitochondrial FAO and display hypoketotic hypoglycemia and hepatic encephalopathy as typical manifestations. In this report, we present a case of CPT1A deficiency presenting jaundice as the first manifestation. A 1.9 years old boy showed jaundice and elevated levels of free and total carnitine were observed. From direct sequencing analysis of CPT1A, two novel mutations, c.1163+1G>A and c.1393G>A (p.Gly465Arg), were identified. At the age of 2.2 years, hypoglycemia, tachycardia, and altered mental status developed just after cranioplasty for craniosynostosis. High glucose infusion rate was required for recovery of his vital signs and mentality. Diet rich in high carbohydrate, low fat and inclusion of medium chain triglyceride oil resulted in improvement in cholestatic hepatitis and since then the boy has shown normal growth velocity and developmental milestones to date.
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Affiliation(s)
- Jong Sub Choi
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Hyeoh Won Yoo
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Kyung Jae Lee
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Jung Min Ko
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Soo Moon
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
| | - Jae Sung Ko
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
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Inborn Errors of Metabolism in the United Arab Emirates: Disorders Detected by Newborn Screening (2011-2014). JIMD Rep 2015; 28:127-135. [PMID: 26589311 DOI: 10.1007/8904_2015_512] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023] Open
Abstract
This study reports on the inborn errors of metabolism (IEM) detected by our national newborn screening between 2011 and 2014. One hundred fourteen patients (55 UAE citizens and 59 residents) were diagnosed during this period. The program was most comprehensive (tested 29 IEM) and universally applied in 2013, giving an incidence of 1 in 1,787 citizens. This relatively high prevalence resulted from the frequent consanguineous marriages (81.5%) among affected families. The following eight disorders accounted for 80% of the entities: biotinidase deficiency (14 of 55), phenylketonuria (11 of 55), 3-methylcrotonyl glycinuria (9 of 55), medium-chain acyl-CoA dehydrogenase deficiency (4 of 55), argininosuccinic aciduria, glutaric aciduria type 1, glutaric aciduria type 2, and methylmalonyl-CoA mutase deficiency (2 of 55 each). Mutation analysis was performed in 48 (87%) of the 55 patients, and 33 distinct mutations were identified. Twenty-nine (88%) mutations were clinically significant and, thus, could be included in our premarital screening. Most mutations were homozygous, except for the biotinidase deficiency. The BTD mutations c.1207T>G (found in citizens) and c.424C>A (found in Somalians) were associated with undetectable biotinidase activity. Thus, the high prevalence of IEM in our region is amenable to newborn and premarital screening, which is expected to halt most of these diseases.
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Zhou S, Xiong L, Xie P, Ambalavanan A, Bourassa CV, Dionne-Laporte A, Spiegelman D, Turcotte Gauthier M, Henrion E, Diallo O, Dion PA, Rouleau GA. Increased missense mutation burden of Fatty Acid metabolism related genes in nunavik inuit population. PLoS One 2015; 10:e0128255. [PMID: 26010953 PMCID: PMC4444093 DOI: 10.1371/journal.pone.0128255] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 04/24/2015] [Indexed: 12/29/2022] Open
Abstract
Background Nunavik Inuit (northern Quebec, Canada) reside along the arctic coastline where for generations their daily energy intake has mainly been derived from animal fat. Given this particular diet it has been hypothesized that natural selection would lead to population specific allele frequency differences and unique variants in genes related to fatty acid metabolism. A group of genes, namely CPT1A, CPT1B, CPT1C, CPT2, CRAT and CROT, encode for three carnitine acyltransferases that are important for the oxidation of fatty acids, a critical step in their metabolism. Methods Exome sequencing and SNP array genotyping were used to examine the genetic variations in the six genes encoding for the carnitine acyltransferases in 113 Nunavik Inuit individuals. Results Altogether ten missense variants were found in genes CPT1A, CPT1B, CPT1C, CPT2 and CRAT, including three novel variants and one Inuit specific variant CPT1A p.P479L (rs80356779). The latter has the highest frequency (0.955) compared to other Inuit populations. We found that by comparison to Asians or Europeans, the Nunavik Inuit have an increased mutation burden in CPT1A, CPT2 and CRAT; there is also a high level of population differentiation based on carnitine acyltransferase gene variations between Nunavik Inuit and Asians. Conclusion The increased number and frequency of deleterious variants in these fatty acid metabolism genes in Nunavik Inuit may be the result of genetic adaptation to their diet and/or the extremely cold climate. In addition, the identification of these variants may help to understand some of the specific health risks of Nunavik Inuit.
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Affiliation(s)
- Sirui Zhou
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
- Département de médecine, Faculté de médecine, Université de Montréal, Montréal (Que), Canada
| | - Lan Xiong
- Département de psychiatrie, Faculté de médecine, Université de Montréal, Montréal (Que), Canada
- Centre de recherche, Institut universitaire en santé mentale de Montréal (Que), Canada
| | - Pingxing Xie
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
- Department of Human Genetics, McGill University, Montréal (Que), Canada
| | - Amirthagowri Ambalavanan
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
- Department of Human Genetics, McGill University, Montréal (Que), Canada
| | - Cynthia V. Bourassa
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
| | | | - Dan Spiegelman
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
| | | | - Edouard Henrion
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
| | - Ousmane Diallo
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
| | - Patrick A. Dion
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
- Department of Neurology and Neurosurgery, McGill University, Montréal (Que), Canada
| | - Guy A. Rouleau
- Montreal Neurological Institute and Hospital, McGill University, Montréal (Que), Canada
- Department of Neurology and Neurosurgery, McGill University, Montréal (Que), Canada
- * E-mail:
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Clemente F, Cardona A, Inchley C, Peter B, Jacobs G, Pagani L, Lawson D, Antão T, Vicente M, Mitt M, DeGiorgio M, Faltyskova Z, Xue Y, Ayub Q, Szpak M, Mägi R, Eriksson A, Manica A, Raghavan M, Rasmussen M, Rasmussen S, Willerslev E, Vidal-Puig A, Tyler-Smith C, Villems R, Nielsen R, Metspalu M, Malyarchuk B, Derenko M, Kivisild T. A Selective Sweep on a Deleterious Mutation in CPT1A in Arctic Populations. Am J Hum Genet 2014; 95:584-589. [PMID: 25449608 DOI: 10.1016/j.ajhg.2014.09.016] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/29/2014] [Indexed: 10/24/2022] Open
Abstract
Arctic populations live in an environment characterized by extreme cold and the absence of plant foods for much of the year and are likely to have undergone genetic adaptations to these environmental conditions in the time they have been living there. Genome-wide selection scans based on genotype data from native Siberians have previously highlighted a 3 Mb chromosome 11 region containing 79 protein-coding genes as the strongest candidates for positive selection in Northeast Siberians. However, it was not possible to determine which of the genes might be driving the selection signal. Here, using whole-genome high-coverage sequence data, we identified the most likely causative variant as a nonsynonymous G>A transition (rs80356779; c.1436C>T [p.Pro479Leu] on the reverse strand) in CPT1A, a key regulator of mitochondrial long-chain fatty-acid oxidation. Remarkably, the derived allele is associated with hypoketotic hypoglycemia and high infant mortality yet occurs at high frequency in Canadian and Greenland Inuits and was also found at 68% frequency in our Northeast Siberian sample. We provide evidence of one of the strongest selective sweeps reported in humans; this sweep has driven this variant to high frequency in circum-Arctic populations within the last 6-23 ka despite associated deleterious consequences, possibly as a result of the selective advantage it originally provided to either a high-fat diet or a cold environment.
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Abstract
Background:Genetic and environmental factors are important determinants of disease distribution. Several disorders associated with ataxia are known to occur more commonly in certain ethnic groups; for example, the disequilibrium syndrome in the Hutterites. The aim of this study was to determine the ethnic and geographic distribution of pediatric patients with chronic ataxia in Manitoba, Canada.Methods:We identified 184 patients less than 17 years-of-age with chronic ataxia during 1991-2008 from multiple sources. Their diagnosis, ethnicity and place of residence were determined following a chart review.Results:Most patients resided in Manitoba (N=177) and the majority in Winnipeg, the provincial capital. Thirty five Aboriginal, 29 Mennonite and 11 Hutterite patients resided in Manitoba. The latter two groups were significantly overrepresented in our cohort. Ataxia telangiectasia, mitochondrial disorders, and non-progressive ataxia of unknown etiology associated with pyramidal tracts signs and developmental delay were significantly more common in Mennonite patients. Four of five patients with neuronal migration disorders associated with chronic ataxia were Aboriginal. Few isolated disorders with chronic ataxia occurred in the 11 Hutterite patients including a Joubert syndrome related disorder.Conclusions:Three disorders associated with chronic ataxia were more prevalent than expected in Mennonites in Manitoba. Few rare disorders were more prevalent in the Hutterite and Aboriginal population. Further research is needed to determine the risk factors underlying these variations in prevalence within different ethnic groups. The unique risk factor profiles of each ethnic group need to be considered in health promotion endeavors.
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Aksentijević D, McAndrew DJ, Karlstädt A, Zervou S, Sebag-Montefiore L, Cross R, Douglas G, Regitz-Zagrosek V, Lopaschuk GD, Neubauer S, Lygate CA. Cardiac dysfunction and peri-weaning mortality in malonyl-coenzyme A decarboxylase (MCD) knockout mice as a consequence of restricting substrate plasticity. J Mol Cell Cardiol 2014; 75:76-87. [PMID: 25066696 PMCID: PMC4169183 DOI: 10.1016/j.yjmcc.2014.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 01/21/2023]
Abstract
UNLABELLED Inhibition of malonyl-coenzyme A decarboxylase (MCD) shifts metabolism from fatty acid towards glucose oxidation, which has therapeutic potential for obesity and myocardial ischemic injury. However, ~40% of patients with MCD deficiency are diagnosed with cardiomyopathy during infancy. AIM To clarify the link between MCD deficiency and cardiac dysfunction in early life and to determine the contributing systemic and cardiac metabolic perturbations. METHODS AND RESULTS MCD knockout mice ((-/-)) exhibited non-Mendelian genotype ratios (31% fewer MCD(-/-)) with deaths clustered around weaning. Immediately prior to weaning (18days) MCD(-/-) mice had lower body weights, elevated body fat, hepatic steatosis and glycogen depletion compared to wild-type littermates. MCD(-/-) plasma was hyperketonemic, hyperlipidemic, had 60% lower lactate levels and markers of cellular damage were elevated. MCD(-/-) hearts exhibited hypertrophy, impaired ejection fraction and were energetically compromised (32% lower total adenine nucleotide pool). However differences between WT and MCD(-/-) converged with age, suggesting that, in surviving MCD(-/-) mice, early cardiac dysfunction resolves over time. These observations were corroborated by in silico modelling of cardiomyocyte metabolism, which indicated improvement of the MCD(-/-) metabolic phenotype and improved cardiac efficiency when switched from a high-fat diet (representative of suckling) to a standard post-weaning diet, independent of any developmental changes. CONCLUSIONS MCD(-/-) mice consistently exhibited cardiac dysfunction and severe metabolic perturbations while on a high-fat, low carbohydrate diet of maternal milk and these gradually resolved post-weaning. This suggests that dysfunction is a common feature of MCD deficiency during early development, but that severity is dependent on composition of dietary substrates.
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Affiliation(s)
- Dunja Aksentijević
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Anja Karlstädt
- Institute of Gender in Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany; Center for Cardiovascular Research, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Liam Sebag-Montefiore
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Rebecca Cross
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Gillian Douglas
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Vera Regitz-Zagrosek
- Institute of Gender in Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany; Center for Cardiovascular Research, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Gary D Lopaschuk
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK.
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Gessner BD, Gillingham MB, Wood T, Koeller DM. Association of a genetic variant of carnitine palmitoyltransferase 1A with infections in Alaska Native children. J Pediatr 2013; 163:1716-21. [PMID: 23992672 DOI: 10.1016/j.jpeds.2013.07.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 06/16/2013] [Accepted: 07/03/2013] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To evaluate whether the arctic variant (c.1436C→T) of carnitine palmitoyltransferase type 1A (CPT1A) is associated with a higher incidence of adverse health outcomes in Alaska Native infants and children. STUDY DESIGN We evaluated health measures from birth certificates (n = 605) and Alaska Medicaid billing claims (n = 427) collected from birth to 2.5 years of age for a cohort of Alaska Native infants with known CPT1A genotype. To account for geographic variations in gene distribution and other variables, data also were evaluated in cohorts. RESULTS When analysis was restricted to residents of nonhub communities in Western and Northern Alaska, children homozygous for the arctic variant experienced more episodes of lower respiratory tract infection than did heterozygous or noncarrier children (5.5 vs 3.7, P = .067) and were more likely to have had otitis media (86% vs 69%, 95% CI 1.4-8.9). Associations were weaker for more homogeneous cohorts. CONCLUSIONS The association of the arctic variant of CPT1A with infectious disease outcomes in children between birth and 2.5 years of age suggests that this variant may play a role in the historically high incidence of these health outcomes among indigenous Arctic populations; further studies will need to assess if this association was confounded by other risk factors.
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Olpin SE. Pathophysiology of fatty acid oxidation disorders and resultant phenotypic variability. J Inherit Metab Dis 2013; 36:645-58. [PMID: 23674167 PMCID: PMC7101856 DOI: 10.1007/s10545-013-9611-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/27/2013] [Accepted: 04/10/2013] [Indexed: 12/16/2022]
Abstract
Fatty acids are a major fuel for the body and fatty acid oxidation is particularly important during fasting, sustained aerobic exercise and stress. The myocardium and resting skeletal muscle utilise long-chain fatty acids as a major source of energy. Inherited disorders affecting fatty acid oxidation seriously compromise the function of muscle and other highly energy-dependent tissues such as brain, nerve, heart, kidney and liver. Such defects encompass a wide spectrum of clinical disease, presenting in the neonatal period or infancy with recurrent hypoketotic hypoglycaemic encephalopathy, liver dysfunction, hyperammonaemia and often cardiac dysfunction. In older children, adolescence or adults there is often exercise intolerance with episodic myalgia or rhabdomyolysis in association with prolonged aerobic exercise or other exacerbating factors. Some disorders are particularly associated with toxic metabolites that may contribute to encephalopathy, polyneuropathy, axonopathy and pigmentary retinopathy. The phenotypic diversity encountered in defects of fat oxidation is partly explained by genotype/phenotype correlation and certain identifiable environmental factors but there remain many unresolved questions regarding the complex interaction of genetic, epigenetic and environmental influences that dictate phenotypic expression. It is becoming increasingly clear that the view that most inherited disorders are purely monogenic diseases is a naive concept. In the future our approach to understanding the phenotypic diversity and management of patients will be more realistically achieved from a polygenic perspective.
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Affiliation(s)
- Simon E Olpin
- Department of Clinical Chemistry, Sheffield Children's Hospital, Sheffield S10 2TH, UK.
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Collins SA, Surmala P, Osborne G, Greenberg C, Bathory LW, Edmunds-Potvin S, Arbour L. Causes and risk factors for infant mortality in Nunavut, Canada 1999-2011. BMC Pediatr 2012; 12:190. [PMID: 23231747 PMCID: PMC3534516 DOI: 10.1186/1471-2431-12-190] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 12/05/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The northern territory Nunavut has Canada's largest jurisdictional land mass with 33,322 inhabitants, of which 85% self-identify as Inuit. Nunavut has rates of infant mortality, postneonatal mortality and hospitalisation of infants for respiratory infections that greatly exceed those for the rest of Canada. The infant mortality rate in Nunavut is 3 times the national average, and twice that of the neighbouring territory, the Northwest Territories. Nunavut has the largest Inuit population in Canada, a population which has been identified as having high rates of Sudden Infant Death Syndrome (SIDS) and infant deaths due to infections. METHODS To determine the causes and potential risk factors of infant mortality in Nunavut, we reviewed all infant deaths (<1 yr) documented by the Nunavut Chief Coroner's Office and the Nunavut Bureau of Statistics (n=117; 1999-2011). Rates were compared to published data for Canada. RESULTS Sudden death in infancy (SIDS/SUDI; 48%) and infection (21%) were the leading causes of infant death, with rates significantly higher than for Canada (2003-2007). Of SIDS/SUDI cases with information on sleep position (n=42) and bed-sharing (n=47), 29 (69%) were sleeping non-supine and 33 (70%) were bed-sharing. Of those bed-sharing, 23 (70%) had two or more additional risk factors present, usually non-supine sleep position. CPT1A P479L homozygosity, which has been previously associated with infant mortality in Alaska Native and British Columbia First Nations populations, was associated with unexpected infant death (SIDS/SUDI, infection) throughout Nunavut (OR:3.43, 95% CI:1.30-11.47). CONCLUSION Unexpected infant deaths comprise the majority of infant deaths in Nunavut. Although the CPT1A P479L variant was associated with unexpected infant death in Nunavut as a whole, the association was less apparent when population stratification was considered. Strategies to promote safe sleep practices and further understand other potential risk factors for infant mortality (P479L variant, respiratory illness) are underway with local partners.
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Affiliation(s)
- Sorcha A Collins
- Department of Medical Genetics, University of British Columbia Island Medical Program, University of Victoria, PO Box 1700 STN CSC, Victoria, BC, V8W 2Y2, Canada
| | - Padma Surmala
- Court Services Division, Department of Justice, Government of Nunavut, Iqaluit, NU, Canada
| | - Geraldine Osborne
- Department of Health and Social Services, Government of Nunavut, Iqaluit, NU, Canada
| | - Cheryl Greenberg
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada
| | | | | | - Laura Arbour
- Department of Medical Genetics, University of British Columbia Island Medical Program, University of Victoria, PO Box 1700 STN CSC, Victoria, BC, V8W 2Y2, Canada
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Sinclair GB, Collins S, Popescu O, McFadden D, Arbour L, Vallance HD. Carnitine palmitoyltransferase I and sudden unexpected infant death in British Columbia First Nations. Pediatrics 2012; 130:e1162-9. [PMID: 23090344 DOI: 10.1542/peds.2011-2924] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Infant mortality in British Columbia (BC) First Nations remains elevated relative to other residents. The p.P479L (c.1436C>T) variant of carnitine palmitoyltransferase 1 (CPT1A) is frequent in some aboriginal populations and may be associated with increased infant deaths. This work was initiated to determine the performance of acylcarnitine profiling for detecting this variant, to determine its frequency in BC, and to determine if it is associated with sudden infant deaths in this population. METHODS Newborn screening cards from all BC First Nations infants in 2004 and all sudden unexpected deaths in BC First Nations infants (1999-2009) were genotyped for the CPT1A p.P479L variant and linked to archival acylcarnitine data. RESULTS The CPT1A p.P479L variant is frequent in BC First Nations but is not evenly distributed, with higher rates in coastal regions (up to 25% homozygosity) with historically increased infant mortality. There is also an overrepresentation of p.P479L homozygotes in unexpected infant deaths from these regions, with an odds ratio of 3.92 (95% confidence interval: 1.69-9.00). Acylcarnitine profiling will identify p.P479L homozygotes with a 94% sensitivity and specificity. CONCLUSIONS The CPT1A p.P479L variant is common to some coastal BC First Nations, and homozygosity for this variant is associated with unexpected death in infancy. The high frequency of this variant in a wide range of coastal aboriginal communities, however, suggests a selective advantage, raising the possibility that this variant may have differing impacts on health depending on the environmental or developmental context.
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Affiliation(s)
- Graham B Sinclair
- Departmens of aPathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia.
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Abstract
Liver dysfunction usually accompanies metabolic decompensation in fatty acid oxidation disorders, including carnitine palmitoyltransferase (CPT) Ia deficiency. Typically, the liver is enlarged with raised plasma transaminase activities and steatosis on histological examination. In contrast, cholestatic jaundice is rare, having only been reported in long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency. We report a 3-year-old boy with CPT Ia deficiency who developed hepatomegaly and cholestatic jaundice following a viral illness. No cause for the jaundice could be found, apart from the fatty acid oxidation disorder. Liver histology showed diffuse, predominately macrovesicular steatosis, hepatocellular and canalicular cholestasis but no bile duct paucity or evidence of large duct obstruction. The liver dysfunction resolved in 4-7 weeks.
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Hannah-Shmouni F, McLeod K, Sirrs S. Recurrent exercise-induced rhabdomyolysis. CMAJ 2012; 184:426-30. [PMID: 22311949 DOI: 10.1503/cmaj.110518] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Fady Hannah-Shmouni
- Adult Metabolic Diseases Clinic, Division of Endocrinology, University of British Columbia, Vancouver, BC.
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Application of Next Generation Sequencing to Molecular Diagnosis of Inherited Diseases. CHEMICAL DIAGNOSTICS 2012; 336:19-45. [DOI: 10.1007/128_2012_325] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Gillingham MB, Hirschfeld M, Lowe S, Matern D, Shoemaker J, Lambert WE, Koeller DM. Impaired fasting tolerance among Alaska native children with a common carnitine palmitoyltransferase 1A sequence variant. Mol Genet Metab 2011; 104:261-4. [PMID: 21763168 PMCID: PMC3197793 DOI: 10.1016/j.ymgme.2011.06.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2011] [Revised: 06/21/2011] [Accepted: 06/22/2011] [Indexed: 11/30/2022]
Abstract
A high prevalence of the sequence variant c.1436C→T in the CPT1A gene has been identified among Alaska Native newborns but the clinical implications of this variant are unknown. We conducted medically supervised fasts in 5 children homozygous for the c.1436C→T variant. Plasma free fatty acids increased normally in these children but their long-chain acylcarnitine and ketone production was significantly blunted. The fast was terminated early in two subjects due to symptoms of hypoglycemia. Homozygosity for the c.1436C→T sequence variant of CPT1A impairs fasting ketogenesis, and can cause hypoketotic hypoglycemia in young children. Trial registration www.clinical trials.gov NCT00653666 "Metabolic Consequences of CPT1A Deficiency"
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Affiliation(s)
- Melanie B Gillingham
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR 97239, USA.
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Lemas DJ, Wiener HW, O'Brien DM, Hopkins S, Stanhope KL, Havel PJ, Allison DB, Fernandez JR, Tiwari HK, Boyer BB. Genetic polymorphisms in carnitine palmitoyltransferase 1A gene are associated with variation in body composition and fasting lipid traits in Yup'ik Eskimos. J Lipid Res 2011; 53:175-84. [PMID: 22045927 DOI: 10.1194/jlr.p018952] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Variants of carnitine palmitoyltransferase 1A (CPT1A), a key hepatic lipid oxidation enzyme, may influence how fatty acid oxidation contributes to obesity and metabolic outcomes. CPT1A is regulated by diet, suggesting interactions between gene variants and diet may influence outcomes. The objective of this study was to test the association of CPT1A variants with body composition and lipids, mediated by consumption of polyunsaturated fatty acids (PUFA). Obesity phenotypes and fasting lipids were measured in a cross-sectional sample of Yup'ik Eskimo individuals (n = 1141) from the Center of Alaska Native Health Research (CANHR) study. Twenty-eight tagging CPT1A SNPs were evaluated with outcomes of interest in regression models accounting for family structure. Several CPT1A polymorphisms were associated with HDL-cholesterol and obesity phenotypes. The P479L (rs80356779) variant was associated with all obesity-related traits and fasting HDL-cholesterol. Interestingly, the association of P479L with HDL-cholesterol was still significant after correcting for body mass index (BMI), percentage body fat (PBF), or waist circumference (WC). Our findings are consistent with the hypothesis that the L479 allele of the CPT1A P479L variant confers a selective advantage that is both cardioprotective (through increased HDL-cholesterol) and associated with reduced adiposity.
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Affiliation(s)
- Dominick J Lemas
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
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Clinical validation of cutoff target ranges in newborn screening of metabolic disorders by tandem mass spectrometry: a worldwide collaborative project. Genet Med 2011; 13:230-54. [PMID: 21325949 DOI: 10.1097/gim.0b013e31820d5e67] [Citation(s) in RCA: 256] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE To achieve clinical validation of cutoff values for newborn screening by tandem mass spectrometry through a worldwide collaborative effort. METHODS Cumulative percentiles of amino acids and acylcarnitines in dried blood spots of approximately 25–30 million normal newborns and 10,742 deidentified true positive cases are compared to assign clinical significance, which is achieved when the median of a disorder range is, and usually markedly outside, either the 99th or the 1st percentile of the normal population. The cutoff target ranges of analytes and ratios are then defined as the interval between selected percentiles of the two populations. When overlaps occur, adjustments are made to maximize sensitivity and specificity taking all available factors into consideration. RESULTS As of December 1, 2010, 130 sites in 45 countries have uploaded a total of 25,114 percentile data points, 565,232 analyte results of true positive cases with 64 conditions, and 5,341 cutoff values. The average rate of submission of true positive cases between December 1, 2008, and December 1, 2010, was 5.1 cases/day. This cumulative evidence generated 91 high and 23 low cutoff target ranges. The overall proportion of cutoff values within the respective target range was 42% (2,269/5,341). CONCLUSION An unprecedented level of cooperation and collaboration has allowed the objective definition of cutoff target ranges for 114 markers to be applied to newborn screening of rare metabolic disorders.
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Tan L, Narayan SB, Chen J, Meyers GD, Bennett MJ. PTC124 improves readthrough and increases enzymatic activity of the CPT1A R160X nonsense mutation. J Inherit Metab Dis 2011; 34:443-7. [PMID: 21253826 DOI: 10.1007/s10545-010-9265-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 12/13/2010] [Accepted: 12/23/2010] [Indexed: 02/06/2023]
Abstract
Deficiency of carnitine palmitoyltransferase 1A (CPT1A) results in impaired hepatic long-chain fatty acid oxidation and ketogenesis. We have previously described a patient with a severe CPT1A phenotype who is homozygous for the nonsense mutation 478 C > T (R160X). It has been known for some time that gentamicin can promote readthrough of nonsense codons. Recently, a new compound (PTC124) with less clinical toxicity than gentamicin has been indicated as a therapy for patients with nonsense mutations for multiple genetic diseases. The study is designed to investigate whether PTC124 can promote readthrough of the R160X CPT1A mutation and increase normal sized CPT1 protein expression and activity in the patient's skin fibroblasts. Our study demonstrated that after both PTC 124 and gentamicin treatment, there was an increase in CPT1 activity in patient fibroblasts to levels that are similar to that of the mild Inuit P479L variant. Our results provide additional evidence for proof of principle that PTC124 is a potential therapeutic agent for treating patients with any genetic condition that results from a nonsense mutation.
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Affiliation(s)
- Lu Tan
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
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Gessner BD, Gillingham MB, Johnson MA, Richards CS, Lambert WE, Sesser D, Rien LC, Hermerath CA, Skeels MR, Birch S, Harding CO, Wood T, Koeller DM. Prevalence and distribution of the c.1436C→T sequence variant of carnitine palmitoyltransferase 1A among Alaska Native infants. J Pediatr 2011; 158:124-9. [PMID: 20843525 DOI: 10.1016/j.jpeds.2010.07.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 06/15/2010] [Accepted: 07/21/2010] [Indexed: 10/19/2022]
Abstract
OBJECTIVES To use genotype analysis to determine the prevalence of the c.1436C→T sequence variant in carnitine palmitoyltransferase 1A (CPT1A) among Alaskan infants, and evaluate the sensitivity of newborn screening by tandem mass spectrometry (MS/MS) to identify homozygous infants. STUDY DESIGN We compared MS/MS and DNA analyses of 2409 newborn blood spots collected over 3 consecutive months. RESULTS Of 2409 infants, 166 (6.9%) were homozygous for the variant, all but one of whom were of Alaska Native race. None of the homozygous infants was identified by MS/MS on the first newborn screen using a C0/C16 + C18 cutoff of 130. Among 633 Alaska Native infants, 165 (26.1%) were homozygous and 218 (34.4%) were heterozygous for the variant. The prevalence was highest in Alaska's northern/western regions (51.2% of 255 infants homozygous; allele frequency, 0.7). CONCLUSIONS The CPT1A c.1436C→T variant is prevalent among some Alaska Native peoples, but newborn screening using current MS/MS cutoffs is not an effective means to identify homozygous infants. The clinical consequences of the partial CPT1A deficiency associated with this variant are unknown. If effects are substantial, revision of newborn screening, including Alaska-specific MS/MS cutoffs and confirmatory genotyping, may be needed.
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Gessner BD, Gillingham MB, Birch S, Wood T, Koeller DM. Evidence for an association between infant mortality and a carnitine palmitoyltransferase 1A genetic variant. Pediatrics 2010; 126:945-51. [PMID: 20937660 DOI: 10.1542/peds.2010-0687] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Alaska Native and other circumpolar indigenous populations have historically experienced high infant mortality rates, for unknown reasons. Through routine newborn screening, Alaskan and Canadian indigenous infants have been found to have a high frequency of a single sequence variant (c.1436C→T) in the gene coding for carnitine palmitoyltransferase type 1A (CPT1A). We sought to determine whether these 2 findings were related. METHODS As part of a quality control exercise at the Alaskan Newborn Metabolic Screening Program, we conducted genotyping for 616 consecutively born, Alaska Native infants and reviewed their medical records. We conducted an ecological analysis comparing Census area-level variant CPT1A allele frequency and historical Alaska Native infant, postneonatal, and neonatal mortality rates. RESULTS Infant death was identified for 5 of 152 infants homozygous for the c.1436C→T sequence variant (33 deaths per 1000 live births), 2 of 219 heterozygous infants (9 deaths per 1000 live births), and 0 of 245 infants carrying no copies of the variant allele (χ(2) = 9.2; P = .01). All 7 cases of infant death had some evidence of an infectious process at the time of death, including 5 with respiratory infections. Census areas with the highest frequency of the variant allele had the highest historical infant, postneonatal, and neonatal mortality rates. CONCLUSIONS Our data provide preliminary evidence that a highly prevalent CPT1A variant found among Alaska Native and other indigenous circumpolar populations may help explain historically high infant mortality rates. Larger definitive studies are needed.
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Affiliation(s)
- Bradford D Gessner
- Alaska Division of Public Health, PO Box 240249, Suite 354, Anchorage, AK 99524, USA.
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