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Abstract
Mitochondrial diseases require customized approaches for reproductive counseling, addressing differences in recurrence risks and reproductive options. The majority of mitochondrial diseases is caused by mutations in nuclear genes and segregate in a Mendelian way. Prenatal diagnosis (PND) or preimplantation genetic testing (PGT) are available to prevent the birth of another severely affected child. In at least 15%-25% of cases, mitochondrial diseases are caused by mitochondrial DNA (mtDNA) mutations, which can occur de novo (25%) or be maternally inherited. For de novo mtDNA mutations, the recurrence risk is low and PND can be offered for reassurance. For maternally inherited, heteroplasmic mtDNA mutations, the recurrence risk is often unpredictable, due to the mitochondrial bottleneck. PND for mtDNA mutations is technically possible, but often not applicable given limitations in predicting the phenotype. Another option for preventing the transmission of mtDNA diseases is PGT. Embryos with mutant load below the expression threshold are being transferred. Oocyte donation is another safe option to prevent the transmission of mtDNA disease to a future child for couples who reject PGT. Recently, mitochondrial replacement therapy (MRT) became available for clinical application as an alternative to prevent the transmission of heteroplasmic and homoplasmic mtDNA mutations.
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Systematic review of outcomes in studies of reproductive genetic carrier screening: Towards development of a core outcome set. Genet Med 2021; 24:1-14. [PMID: 34906455 DOI: 10.1016/j.gim.2021.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/09/2021] [Accepted: 09/10/2021] [Indexed: 01/08/2023] Open
Abstract
PURPOSE Current practice recommendations support the widespread implementation of reproductive genetic carrier screening (RGCS). These consensus-based recommendations highlight a research gap, with findings from current studies being insufficient to meet the standard required for more rigorous evidence-based recommendations. This systematic review assessed methodological aspects of studies on RGCS to inform the need for a core outcome set. METHODS We conducted a systematic search to identify peer-reviewed published studies offering population-based RGCS. Study designs, outcomes, and measurement methods were extracted. A narrative synthesis was conducting using an existing outcome taxonomy and criteria used in the evaluation of genetic screening programs as frameworks. RESULTS Sixty-five publications were included. We extracted 120 outcomes representing 24 outcome domains. Heterogeneity in outcome selection, measurement methods and time points of assessment was extensive. Quality appraisal raised concerns for bias. We found that reported outcomes had limited applicability to criteria used to evaluate genetic screening programs. CONCLUSION Despite a large body of literature, diverse approaches to research have limited the conclusions that can be cumulatively drawn from this body of evidence. Consensus regarding meaningful outcomes for evaluation of RGCS would be a valuable first step in working towards evidence-based practice recommendations, supporting the development of a core outcome set.
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van Walree ES, Dombrowsky G, Jansen IE, Mirkov MU, Zwart R, Ilgun A, Guo D, Clur SAB, Amin AS, Savage JE, van der Wal AC, Waisfisz Q, Maugeri A, Wilsdon A, Bu'Lock FA, Hurles ME, Dittrich S, Berger F, Audain Martinez E, Christoffels VM, Hitz MP, Milewicz DM, Posthuma D, Meijers-Heijboer H, Postma AV, Mathijssen IB. Germline variants in HEY2 functional domains lead to congenital heart defects and thoracic aortic aneurysms. Genet Med 2020; 23:103-110. [PMID: 32820247 PMCID: PMC8804301 DOI: 10.1038/s41436-020-00939-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/31/2020] [Accepted: 07/31/2020] [Indexed: 12/19/2022] Open
Abstract
Purpose In this study we aimed to establish the genetic cause of a myriad of cardiovascular defects prevalent in individuals from a genetically isolated population, who were found to share a common ancestor in 1728. Methods Trio genome sequencing was carried out in an index patient with critical congenital heart disease (CHD), family members had either exome or Sanger sequencing. To confirm enrichment, we performed a gene-based association test and meta-analysis in two independent validation cohorts: one with 2685 CHD cases versus 4370 controls, and the other 326 cases with familial thoracic aortic aneurysms (FTAA) and dissections versus 570 ancestry-matched controls. Functional consequences of identified variants were evaluated using expression studies. Results We identified a loss-of-function variant in the Notch target transcription factor-encoding gene HEY2. The homozygous state (n=3) causes life-threatening congenital heart defects, while 80% of heterozygous carriers (n=20) had cardiovascular defects, mainly CHD and FTAA of the ascending aorta. We confirm enrichment of rare risk variants in HEY2 functional domains after meta-analysis (meta-SKAT p=0.018). Furthermore, we show that several identified variants lead to dysregulation of repression by HEY2. Conclusion A homozygous germline loss-of-function variant in HEY2 leads to critical CHD. The majority of heterozygotes show a myriad of cardiovascular defects.
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Affiliation(s)
- Eva S van Walree
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands. .,Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands.
| | - Gregor Dombrowsky
- Department of Congenital Heart Disease and Pediatric Cardiology, Universitätsklinikum Schleswig-Holstein Kiel, Kiel, Germany
| | - Iris E Jansen
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands.,Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Maša Umićević Mirkov
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
| | - Rob Zwart
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Aho Ilgun
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Dongchuan Guo
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Sally-Ann B Clur
- Department of Pediatric Cardiology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Ahmed S Amin
- Department of Clinical and Experimental Cardiology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Jeanne E Savage
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
| | - Allard C van der Wal
- Department of Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Quinten Waisfisz
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Medisch Centrum, Amsterdam, The Netherlands
| | - Alessandra Maugeri
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Medisch Centrum, Amsterdam, The Netherlands
| | - Anna Wilsdon
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Frances A Bu'Lock
- East Midlands Congenital Heart Centre and University of Leicester, Glenfield Hospital, Leicester, United Kingdom
| | - Matthew E Hurles
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Sven Dittrich
- Department of Pediatric Cardiology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Felix Berger
- German Heart Center Berlin, Department of Congenital Heart Disease, Pediatric Cardiology, Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany
| | - Enrique Audain Martinez
- Department of Congenital Heart Disease and Pediatric Cardiology, Universitätsklinikum Schleswig-Holstein Kiel, Kiel, Germany
| | - Vincent M Christoffels
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Marc-Philip Hitz
- Department of Congenital Heart Disease and Pediatric Cardiology, Universitätsklinikum Schleswig-Holstein Kiel, Kiel, Germany
| | - Dianna M Milewicz
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Daniëlle Posthuma
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
| | - Hanne Meijers-Heijboer
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Medisch Centrum, Amsterdam, The Netherlands
| | - Alex V Postma
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Inge B Mathijssen
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
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4
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Nijmeijer SCM, Conijn T, Lakeman P, Henneman L, Wijburg FA, Haverman L. Attitudes of relatives of mucopolysaccharidosis type III patients toward preconception expanded carrier screening. Eur J Hum Genet 2020; 28:1331-1340. [PMID: 32483342 PMCID: PMC7609293 DOI: 10.1038/s41431-020-0648-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 04/28/2020] [Indexed: 11/25/2022] Open
Abstract
Preconception expanded carrier screening (ECS) aims to detect carrier couples of autosomal recessive (AR) disorders before pregnancy in order to increase reproductive autonomy of prospective parents. Genetic knowledge and knowledge gained from experience influence decision making on participation in genetic testing and understanding carrier test results. In this study we assessed whether parents and relatives of patients with the severe AR condition mucopolysaccharidosis type III (MPS III), who are expected to have genetic and experiential knowledge, have more positive attitudes toward ECS than the Dutch reference group. Parents of all MPS III patients known to the Dutch expert center were invited to participate and asked to invite first and second degree relatives. The online questionnaire started with an educational text, and assessed attitudes toward ECS, genetic knowledge and perceived MPS III severity. Results were compared with the Dutch population. Parents and relatives of MPS III patients (n = 159) scored higher on the genetic knowledge test and perceived MPS III as more severe compared with the general Dutch population (n = 781). Parents and relatives reported to be more likely to participate in ECS (84.3% and 62.5%, respectively) compared with the public (31%) (p < 0.001). Being a relative of a MPS III patient was the strongest variable in the regression analyses for intended ECS participation. Our results show that genetic knowledge influences ECS decision making. Therefore, appropriate information on ECS and genetic counseling is needed to enable prospective parents from the general population, including relatives of patients with severe hereditary disorders, to make informed decisions.
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Affiliation(s)
- Stephanie C M Nijmeijer
- Amsterdam UMC, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Thirsa Conijn
- Amsterdam UMC, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.,Amsterdam UMC, Psychosocial Department, Emma Children's Hospital, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Phillis Lakeman
- Amsterdam UMC, Department of Clinical Genetics, Amsterdam Reproduction and Development Research Institute, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Lidewij Henneman
- Amsterdam UMC, Department of Clinical Genetics, Amsterdam Reproduction and Development Research Institute, Vrije Universiteit Amsterdam, De Boelelaan 1117, Amsterdam, The Netherlands
| | - Frits A Wijburg
- Amsterdam UMC, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.
| | - Lotte Haverman
- Amsterdam UMC, Psychosocial Department, Emma Children's Hospital, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
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5
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Zhytnik L, Simm K, Salumets A, Peters M, Märtson A, Maasalu K. Reproductive options for families at risk of Osteogenesis Imperfecta: a review. Orphanet J Rare Dis 2020; 15:128. [PMID: 32460820 PMCID: PMC7251694 DOI: 10.1186/s13023-020-01404-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/11/2020] [Indexed: 02/07/2023] Open
Abstract
Background Osteogenesis Imperfecta (OI) is a rare genetic disorder involving bone fragility. OI patients typically suffer from numerous fractures, skeletal deformities, shortness of stature and hearing loss. The disorder is characterised by genetic and clinical heterogeneity. Pathogenic variants in more than 20 different genes can lead to OI, and phenotypes can range from mild to lethal forms. As a genetic disorder which undoubtedly affects quality of life, OI significantly alters the reproductive confidence of families at risk. The current review describes a selection of the latest reproductive approaches which may be suitable for prospective parents faced with a risk of OI. The aim of the review is to alleviate suffering in relation to family planning around OI, by enabling prospective parents to make informed and independent decisions. Main body The current review provides a comprehensive overview of possible reproductive options for people with OI and for unaffected carriers of OI pathogenic genetic variants. The review considers reproductive options across all phases of family planning, including pre-pregnancy, fertilisation, pregnancy, and post-pregnancy. Special attention is given to the more modern techniques of assisted reproduction, such as preconception carrier screening, preimplantation genetic testing for monogenic diseases and non-invasive prenatal testing. The review outlines the methodologies of the different reproductive approaches available to OI families and highlights their advantages and disadvantages. These are presented as a decision tree, which takes into account the autosomal dominant and autosomal recessive nature of the OI variants, and the OI-related risks of people without OI. The complex process of decision-making around OI reproductive options is also discussed from an ethical perspective. Conclusion The rapid development of molecular techniques has led to the availability of a wide variety of reproductive options for prospective parents faced with a risk of OI. However, such options may raise ethical concerns in terms of methodologies, choice management and good clinical practice in reproductive care, which are yet to be fully addressed.
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Affiliation(s)
- Lidiia Zhytnik
- Clinic of Traumatology and Orthopaedics, Tartu University Hospital, Tartu, Estonia.
| | - Kadri Simm
- Institute of Philosophy and Semiotics, Faculty of Arts and Humanities, University of Tartu, Tartu, Estonia.,Centre of Ethics, University of Tartu, Tartu, Estonia
| | - Andres Salumets
- Competence Centre on Health Technologies, Tartu, Estonia.,Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia.,Institute of Genomics, University of Tartu, Tartu, Estonia.,COMBIVET ERA Chair, Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia
| | - Maire Peters
- Competence Centre on Health Technologies, Tartu, Estonia.,Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Aare Märtson
- Clinic of Traumatology and Orthopaedics, Tartu University Hospital, Tartu, Estonia.,Department of Traumatology and Orthopaedics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Katre Maasalu
- Clinic of Traumatology and Orthopaedics, Tartu University Hospital, Tartu, Estonia.,Department of Traumatology and Orthopaedics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
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6
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Talib M, Boon CJF. Retinal Dystrophies and the Road to Treatment: Clinical Requirements and Considerations. Asia Pac J Ophthalmol (Phila) 2020; 9:159-179. [PMID: 32511120 PMCID: PMC7299224 DOI: 10.1097/apo.0000000000000290] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/01/2020] [Indexed: 12/15/2022] Open
Abstract
: Retinal dystrophies (RDs) comprise relatively rare but devastating causes of progressive vision loss. They represent a spectrum of diseases with marked genetic and clinical heterogeneity. Mutations in the same gene may lead to different diagnoses, for example, retinitis pigmentosa or cone dystrophy. Conversely, mutations in different genes may lead to the same phenotype. The age at symptom onset, and the rate and characteristics of peripheral and central vision decline, may vary widely per disease group and even within families. For most RD cases, no effective treatment is currently available. However, preclinical studies and phase I/II/III gene therapy trials are ongoing for several RD subtypes, and recently the first retinal gene therapy has been approved by the US Food and Drug Administration for RPE65-associated RDs: voretigene neparvovec-rzyl (Luxturna). With the rapid advances in gene therapy studies, insight into the phenotypic spectrum and long-term disease course is crucial information for several RD types. The vast clinical heterogeneity presents another important challenge in the evaluation of potential efficacy in future treatment trials, and in establishing treatment candidacy criteria. This perspective describes these challenges, providing detailed clinical descriptions of several forms of RD that are caused by genes of interest for ongoing and future gene or cell-based therapy trials. Several ongoing and future treatment options will be described.
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Affiliation(s)
- Mays Talib
- Department of Ophthalmology, Leiden, The Netherlands
| | - Camiel J F Boon
- Department of Ophthalmology, Leiden, The Netherlands
- Department of Ophthalmology, Amsterdam UMC, Academic Medical Center, University of Amsterdam. Amsterdam, The Netherlands
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7
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Delatycki MB, Alkuraya F, Archibald A, Castellani C, Cornel M, Grody WW, Henneman L, Ioannides AS, Kirk E, Laing N, Lucassen A, Massie J, Schuurmans J, Thong M, Langen I, Zlotogora J. International perspectives on the implementation of reproductive carrier screening. Prenat Diagn 2019; 40:301-310. [DOI: 10.1002/pd.5611] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/22/2019] [Accepted: 11/07/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Martin B. Delatycki
- Victorian Clinical Genetics Services Parkville Victoria Australia
- Murdoch Children's Research Institute Parkville Victoria Australia
- Department of PaediatricsUniversity of Melbourne Parkville Victoria Australia
| | - Fowzan Alkuraya
- Department of GeneticsKing Faisal Specialist Hospital and Research Centre Riyadh Saudi Arabia
- Saudi Human Genome ProgramKing Abdulaziz City for Science and Technology Riyadh Saudi Arabia
- College of MedicineAlfaisal University Riyadh Saudi Arabia
| | - Alison Archibald
- Victorian Clinical Genetics Services Parkville Victoria Australia
- Murdoch Children's Research Institute Parkville Victoria Australia
- Department of PaediatricsUniversity of Melbourne Parkville Victoria Australia
| | - Carlo Castellani
- Cystic Fibrosis CentreIRCCS Istituto Giannina Gaslini Genoa Italy
| | - Martina Cornel
- Department of Clinical GeneticsAmsterdam UMC, Vrije Universiteit Amsterdam Amsterdam The Netherlands
- Amsterdam Reproduction and Development Research Institute Amsterdam The Netherlands
| | - Wayne W. Grody
- Divisions of Medical Genetics and Molecular Diagnostics, Departments of Pathology and Laboratory Medicine, Pediatrics, and Human GeneticsUCLA School of Medicine Los Angeles California USA
- UCLA Institute for Society and Genetics, Molecular Diagnostic Laboratories and Clinical Genomics CenterUCLA Medical Center Los Angeles California USA
| | - Lidewij Henneman
- Department of Clinical GeneticsAmsterdam UMC, Vrije Universiteit Amsterdam Amsterdam The Netherlands
- Amsterdam Reproduction and Development Research Institute Amsterdam The Netherlands
| | | | - Edwin Kirk
- Sydney Children's Hospital Randwick New South Wales Australia
- New South Wales Health Pathology Randwick New South Wales Australia
- School of Women's and Children's HealthUniversity of New South Wales Randwick New South Wales Australia
| | - Nigel Laing
- University of Western Australia Centre for Medical Research and Harry Perkins Institute of Medical ResearchQEII Medical Centre Nedlands Western Australia Australia
- Neurogenetic Unit, Department of Diagnostic Genomics, PathWest Laboratory MedicineQEII Medical Centre Nedlands Western Australia Australia
| | - Anneke Lucassen
- Faculty of Medicine, Southampton Medical SchoolUniversity of Southampton Southampton UK
| | - John Massie
- Murdoch Children's Research Institute Parkville Victoria Australia
- Department of PaediatricsUniversity of Melbourne Parkville Victoria Australia
- Department of Respiratory MedicineRoyal Children's Hospital Parkville Victoria Australia
| | - Juliette Schuurmans
- Faculty of Medicine, Southampton Medical SchoolUniversity of Southampton Southampton UK
- Department of Genetics, University Medical Center GroningenUniversity of Groningen Groningen The Netherlands
| | - Meow‐Keong Thong
- Genetics and Metabolism Unit, Department of Paediatrics, Faculty of MedicineUniversity of Malaya Kuala Lumpur Malaysia
| | - Irene Langen
- Department of Genetics, University Medical Center GroningenUniversity of Groningen Groningen The Netherlands
| | - Joël Zlotogora
- Hadassah‐Hebrew University Medical School Jerusalem Israel
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8
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Plantinga M, Birnie E, Schuurmans J, Buitenhuis AH, Boersma E, Lucassen AM, Verkerk MA, van Langen IM, Ranchor AV. Expanded carrier screening for autosomal recessive conditions in health care: Arguments for a couple-based approach and examination of couples' views. Prenat Diagn 2019; 39:369-378. [PMID: 30756401 PMCID: PMC6593986 DOI: 10.1002/pd.5437] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 02/01/2019] [Accepted: 02/05/2019] [Indexed: 12/17/2022]
Abstract
Background Expanded carrier screening (ECS) is aimed at detecting carrier states for autosomal recessive (AR) or X‐linked conditions in couples from the general population planning a pregnancy. ECS is currently usually offered on an individual basis despite the fact that, for AR conditions, only carrier couples are at risk of affected offspring. In this paper, we present a couple‐based ECS test‐offer for AR conditions, where results are offered as couple‐results only, and describe how couples view such an offer. Methods and results An online survey covering attitudes, perceived difficulty, and intention to take up couple‐based ECS was used to examine couples' views. Results show that in 76% of the participating couples there is no objection at all towards receiving couple‐results only. Most couples display similar views. Observed discrepancies usually involved one of the couple members having a positive view, whilst the other was neutral. Although views stayed strikingly stable after discussion, the partner's opinion was regarded as important in deciding whether or not to have testing. Conclusion This study shows that most couples do not object to receiving couple rather than individual ECS results, have similar views towards the offer, and are able to discuss differences in views and intentions. What's already known about this topic?
Expanded carrier screening (ECS) has become widely available ECS is usually offered on individual basis, and individual carrier states are reported Views of potential individual users have been researched
What does this study add?
A couple‐based ECS test‐offer for autosomal recessive conditions, where results are offered as couple‐results only An examination of couples' views towards this offer: most couples do not object to receiving couple‐results only
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Affiliation(s)
- Mirjam Plantinga
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Erwin Birnie
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Juliette Schuurmans
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Clinical Ethics and Law, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Anne H Buitenhuis
- Department of Health Psychology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Elise Boersma
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Anneke M Lucassen
- Clinical Ethics and Law, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Marian A Verkerk
- Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Irene M van Langen
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Adelita V Ranchor
- Department of Health Psychology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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9
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Nijmeijer SCM, Conijn T, Lakeman P, Henneman L, Wijburg FA, Haverman L. Attitudes of the general population towards preconception expanded carrier screening for autosomal recessive disorders including inborn errors of metabolism. Mol Genet Metab 2019; 126:14-22. [PMID: 30563741 DOI: 10.1016/j.ymgme.2018.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND A substantial number of severely debilitating and often ultimately fatal inborn errors of metabolism (IEMs) still lack an effective disease-modifying treatment. Informing couples before a pregnancy about an increased risk of having a child with an inherited disorder is now feasible by preconception expanded carrier screening (ECS). While knowledge about carrier status enhances reproductive autonomy, it may also result in ethical dilemmas. The purpose of this study was to assess the attitudes of the general Dutch population towards preconception ECS and to investigate which factors influence these attitudes. METHODS Data collection was carried out in collaboration with a market research agency. In total, 1188 Dutch individuals of reproductive age (18-45 years) were invited by email to complete an online ECS questionnaire in 2016. Prior to the start of the questionnaire, a written explanation of the concepts of autosomal recessive (AR) inheritance, carrier status and ECS was presented. RESULTS The questionnaire was completed by 781 individuals (65.7%), of whom 31% indicated they would take an ECS test themselves. In addition, 55% agreed that ECS should be offered to all prospective parents. The most frequently selected argument in favor of ECS (47.2%) was that participants want to spare a child from a life with a severe hereditary disorder. The reason most often mentioned not to participate in ECS (48%) was that participants reported not having a hereditary disorder in the family. The majority preferred receiving individual test results above a couple-based disclosure method in which participants receive the carrier status results only when they are a carrier couple of the same disorder. Participants with religious beliefs were less likely to participate in ECS, whereas participants who were considering a (future) pregnancy were more likely to participate. CONCLUSION Our study demonstrates an overall positive attitude among participants of reproductive age in the general Dutch population towards preconception ECS. A striking misconception is that many of the participants believe that ECS is of interest only for those with a positive family history of one of the hereditary disorders. This finding emphasizes the importance of providing understandable, balanced information and education to the general public regarding the concepts of inheritance when presenting the option of carrier screening. Our results provide valuable insights that can be used in the debate about the responsible implementation of preconception ECS for AR disorders, including IEMs.
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Affiliation(s)
- Stephanie C M Nijmeijer
- Amsterdam UMC, University of Amsterdam, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", Meibergdreef 9, Amsterdam, Netherlands.
| | - Thirsa Conijn
- Amsterdam UMC, University of Amsterdam, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", Meibergdreef 9, Amsterdam, Netherlands.
| | - Phillis Lakeman
- Amsterdam UMC, University of Amsterdam, Clinical Genetics, Amsterdam Reproduction and Development Research Institute, Meibergdreef 9, Amsterdam, Netherlands.
| | - Lidewij Henneman
- Amsterdam UMC, Vrije Universiteit Amsterdam, Clinical Genetics, Amsterdam Reproduction and Development Research Institute, De Boelelaan 1117, Amsterdam, Netherlands.
| | - Frits A Wijburg
- Amsterdam UMC, University of Amsterdam, Pediatric Metabolic Diseases, Emma Children's Hospital and Amsterdam Lysosome Center "Sphinx", Meibergdreef 9, Amsterdam, Netherlands.
| | - Lotte Haverman
- Amsterdam UMC, University of Amsterdam, Psychosocial Department, Emma Children's Hospital, Meibergdreef 9, Amsterdam, Netherlands.
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10
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van Dijk T, Baas F, Barth PG, Poll-The BT. What's new in pontocerebellar hypoplasia? An update on genes and subtypes. Orphanet J Rare Dis 2018; 13:92. [PMID: 29903031 PMCID: PMC6003036 DOI: 10.1186/s13023-018-0826-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 05/16/2018] [Indexed: 12/25/2022] Open
Abstract
Background Pontocerebellar hypoplasia (PCH) describes a rare, heterogeneous group of neurodegenerative disorders mainly with a prenatal onset. Patients have severe hypoplasia or atrophy of cerebellum and pons, with variable involvement of supratentorial structures, motor and cognitive impairments. Based on distinct clinical features and genetic causes, current classification comprises 11 types of PCH. Main text In this review we describe the clinical, neuroradiological and genetic characteristics of the different PCH subtypes, summarize the differential diagnosis and reflect on potential disease mechanisms in PCH. Seventeen PCH-related genes are now listed in the OMIM database, most of them have a function in RNA processing or translation. It is unknown why defects in these apparently ubiquitous processes result in a brain-specific phenotype. Conclusions Many new PCH related genes and phenotypes have been described due to the appliance of next generation sequencing techniques. By including such a broad range of phenotypes, including non-degenerative and postnatal onset disorders, the current classification gives rise to confusion. Despite the discovery of new pathways involved in PCH, treatment is still symptomatic. However, correct diagnosis of PCH is important to provide suitable care and counseling regarding prognosis, and offer appropriate (prenatal) genetic testing to families.
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Affiliation(s)
- Tessa van Dijk
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands.,Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Frank Baas
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter G Barth
- Department of Pediatric Neurology, Academic Medical Center, Amsterdam, The Netherlands
| | - Bwee Tien Poll-The
- Department of Pediatric Neurology, Academic Medical Center, Amsterdam, The Netherlands.
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11
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Verdonk P, Metselaar S, Storms O, Bartels E. Reproductive choices: a qualitative study of Dutch Moroccan and Turkish consanguineously married women's perspectives on preconception carrier screening. BMC WOMENS HEALTH 2018; 18:79. [PMID: 29855391 PMCID: PMC5984385 DOI: 10.1186/s12905-018-0574-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 05/21/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Cousin marriages, in the Netherlands most frequently between Turkish or Moroccan couples, are at higher risk of having offspring with recessive disorders. Often, these couples not perceive or accept this risk, and it is hardly considered a reason to refrain from family marriages. Preconception carrier screening (PCS) is offered to Jewish groups, and more recently in the Netherlands, to genetically isolated communities. In this study, Dutch Moroccan and Turkish women's perspectives on preconception carrier screening (PCS) and reproductive choices were explored. METHODS Individual interviews were held with Dutch Turkish and Moroccan consanguineously married women (n = 10) and seven group discussions with Turkish and Moroccan women (n = 86). Transcripts and notes were analyzed thematically. RESULTS All women welcomed PCS particularly for premarital genetic screening; regardless of possible reproductive choices, they prefer information about their future child's health. Their perspectives on reproductive choices on the basis of screening results are diverse: refraining from having children is not an option, in vitro fertilization (IVF) combined with pre-implantation genetic diagnosis (PGD) was welcomed, while prenatal genetic diagnosis (PND), termination of pregnancy (TOP), in vitro fertilization with a donor egg cell, artificial insemination with donor sperm (AID), and adoption, were generally found to be unacceptable. Besides, not taking any special measures and preparing for the possibility of having a disabled child are also becoming optional now rather than being the default option. CONCLUSIONS The women's preference for PCS for premarital screening as well as their outspokenness about not marrying or even divorcing when both partners appear to be carriers is striking. Raising awareness (of consanguinity, PCS and the choice for reproductive options), and providing information, screening and counseling sensitive to this target group and their preferences are essential in the provision of effective health care.
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Affiliation(s)
- Petra Verdonk
- Department of Medical Humanities, Amsterdam Public Health research institute, School of Medical Sciences, Boelelaan 1089a, 1081, HV, Amsterdam, The Netherlands.
| | - Suzanne Metselaar
- Department of Medical Humanities, Amsterdam Public Health research institute, Boelelaan 1089a, 1081, HV, Amsterdam, The Netherlands
| | - Oka Storms
- Department of Social and Cultural Anthropology, VU University, De Boelelaan 1105, 1081, HV, Amsterdam, The Netherlands.,MOVISIE Netherlands Centre for Social Development, Catharijnesingel 47, 3511, GC, Utrecht, The Netherlands
| | - Edien Bartels
- Department of Social and Cultural Anthropology, VU University, De Boelelaan 1105, 1081, HV, Amsterdam, The Netherlands
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12
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Mathijssen IB, Holtkamp KCA, Ottenheim CPE, van Eeten-Nijman JMC, Lakeman P, Meijers-Heijboer H, van Maarle MC, Henneman L. Preconception carrier screening for multiple disorders: evaluation of a screening offer in a Dutch founder population. Eur J Hum Genet 2018; 26:166-175. [PMID: 29321671 DOI: 10.1038/s41431-017-0056-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/08/2017] [Accepted: 11/13/2017] [Indexed: 11/09/2022] Open
Abstract
Technological developments have enabled carrier screening for multiple disorders. This study evaluated experiences with a preconception carrier screening offer for four recessive disorders in a Dutch founder population. Questionnaires were completed by 182 attendees pretesting and posttesting and by 137 non-attendees. Semistructured interviews were conducted with seven of the eight carrier couples. Attendees were mainly informed about the existence of screening by friends/colleagues (49%) and family members (44%). Familiarity with the genetic disorders was high. Knowledge after counseling increased (p < 0.001); however, still 9%, compared to 29% before counseling, wrongly mentioned an increased risk of having an affected child if both parents are carriers of different disorders. Most attendees (97%) recalled their test results correctly, but two couples reported being carrier of another disorder than reported. Overall, 63% felt worried while waiting for results but anxiety levels returned to normal afterwards. In all, 2/39 (5%) carriers felt less healthy. Screened individuals were very satisfied; they did not regret testing (97%) and would recommend testing to others (97%). The majority (94%) stated that couples should always have a pretest consultation, preferably by a genetic counselor rather than their general practitioner (83%). All carrier couples made reproductive decisions based on their results. Main reason for non-attendance was unawareness of the screening offer. With expanded carrier screening, adequately informing couples pretest and posttesting is of foremost importance. Close influencers (family/friends) can be used to raise awareness of a screening offer. Our findings provide lessons for the implementation of expanded carrier screening panels in other communities and other settings.
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Affiliation(s)
- Inge B Mathijssen
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands.
| | - Kim C A Holtkamp
- Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands.,Amsterdam Public Health Research Institute, VU University Medical Center, Amsterdam, The Netherlands
| | - Cecile P E Ottenheim
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | | | - Phillis Lakeman
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Hanne Meijers-Heijboer
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands.,Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands
| | - Merel C van Maarle
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Lidewij Henneman
- Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands.,Amsterdam Public Health Research Institute, VU University Medical Center, Amsterdam, The Netherlands
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13
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Nijmeijer SCM, Wijburg FA. Mucopolysaccharidosis type III: current clinical trials, challenges and recommendations. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2018.1411797] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Stephanie CM Nijmeijer
- Department of Pediatric Metabolic Diseases, Emma Children’s Hospital and Amsterdam Lysosome Center ‘Sphinx,’ Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Frits A Wijburg
- Department of Pediatric Metabolic Diseases, Emma Children’s Hospital and Amsterdam Lysosome Center ‘Sphinx,’ Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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14
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Holtkamp KCA, Mathijssen IB, Lakeman P, van Maarle MC, Dondorp WJ, Henneman L, Cornel MC. Factors for successful implementation of population-based expanded carrier screening: learning from existing initiatives. Eur J Public Health 2017; 27:372-377. [PMID: 27485720 PMCID: PMC5421354 DOI: 10.1093/eurpub/ckw110] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Background: Carrier screening for autosomal recessive disorders aims to facilitate reproductive decision-making by identifying couples with a 1-in-4 risk in every pregnancy of having an affected child. Except for a few countries or regions, carrier screening is not widely offered and is mostly ancestry-based. Technological advances enable carrier screening for multiple diseases simultaneously allowing universal screening regardless of ancestry (population-based expanded carrier screening). It is important to study how this can be successfully implemented. This study therefore aims to identify critical factors involved in successful implementation, from a user perspective, by learning from already implemented initiatives. Methods: Factors associated with successful implementation were identified by: (i) a literature review and (ii) two case studies; studying experiences with carrier screening in two high-risk communities (a Dutch founder population and the Ashkenazi Jewish population), including a survey among community members. Results: Factors identified were familiarity with (specific) genetic diseases and its availability, high perceived benefits of screening (e.g. screening avoids much suffering), acceptance of reproductive options, perceived risk of being a carrier and low perceived social barriers (e.g. stigmatization). In contrast to the Jewish community, the initial demand for screening in the Dutch founder population did not entirely come from the community itself. However, the large social cohesion of the community facilitated the implementation process. Conclusion: To ensure successful implementation of population-based expanded carrier screening, efforts should be made to increase knowledge about genetic diseases, create awareness and address personal benefits of screening in a non-directive way.
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Affiliation(s)
- Kim C A Holtkamp
- Department of Clinical Genetics, Section of Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Inge B Mathijssen
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Phillis Lakeman
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Merel C van Maarle
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Wybo J Dondorp
- Department of Health, Ethics & Society, Research Institutes CAPHRI and GROW, Maastricht University, Maastricht, The Netherlands
| | - Lidewij Henneman
- Department of Clinical Genetics, Section of Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Martina C Cornel
- Department of Clinical Genetics, Section of Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
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15
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With expanded carrier screening, founder populations run the risk of being overlooked. J Community Genet 2017; 8:327-333. [PMID: 28555434 PMCID: PMC5614881 DOI: 10.1007/s12687-017-0309-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/16/2017] [Indexed: 11/25/2022] Open
Abstract
Genetically isolated populations exist worldwide. Specific genetic disorders, including rare autosomal recessive disorders may have high prevalences in these populations. We searched for Dutch genetically isolated populations and their autosomal recessive founder mutations. We investigated whether these founder mutations are covered in the (preconception) expanded carrier screening tests of five carrier screening providers. Our results show that the great majority of founder mutations are not covered in these screening panels, and these panels may thus not be appropriate for use in founder populations. It is therefore important to be aware of founder mutations in a population when offering carrier tests.
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16
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Tamura D, Khan SG, DiGiovanna JJ. Molecular diagnosis of xeroderma pigmentosum variant in an isolated population: the interface between precision medicine and public health. Br J Dermatol 2017; 176:1125-1126. [PMID: 28504392 DOI: 10.1111/bjd.15435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- D Tamura
- DNA Repair Section, Dermatology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
| | - S G Khan
- DNA Repair Section, Dermatology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
| | - J J DiGiovanna
- DNA Repair Section, Dermatology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
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17
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Stakeholder perspectives on the implementation of genetic carrier screening in a changing landscape. BMC Health Serv Res 2017; 17:146. [PMID: 28209157 PMCID: PMC5314610 DOI: 10.1186/s12913-017-2083-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 02/09/2017] [Indexed: 01/24/2023] Open
Abstract
Background In most countries, genetic carrier screening is neither offered, nor embedded in mainstream healthcare. Technological developments have triggered a two-fold transition in carrier screening: the expansion from screening one single disorder to many disorders simultaneously, and offering screening universally, regardless of ancestry. This study aims to identify general and population-specific barriers and needs reflected by stakeholders regarding the implementation of carrier screening in a changing landscape. Methods Seventeen semi-structured interviews were conducted with Dutch key stakeholders working in the practical and scientific field of carrier screening. The constellation approach was used to categorise barriers and needs into three levels: culture, structure and practice. Results Barriers on a cultural level include: undecidedness about the desirability of carrier screening, and a lack of priority of screening in mainstream healthcare. On a structural level barriers included: need for organisational structures in healthcare for embedding carrier screening, need for guidelines, financial structures, practical tools for overcoming challenges during counselling, and a need for training and education of both professionals and the public. A lack of demand for screening by the public, and a need for a division of responsibilities were barriers on a practical level. Conclusion The absence of a collective sense of urgency for genetic carrier screening, a lack of organisational structures, and uncertainty or even disagreement about the responsibilities seem to be important barriers in the implementation of carrier screening. Stakeholders therefore suggest that change agents should be formally acknowledged to strategically plan broadening of current initiatives and attune different stakeholders. Electronic supplementary material The online version of this article (doi:10.1186/s12913-017-2083-9) contains supplementary material, which is available to authorized users.
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18
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Affiliation(s)
| | - Maria Daniela D'Agostino
- McGill University Department of Human Genetics and McGill University Health Center, Department of Medical Genetics, Montreal, QC, Canada
| | - Nancy Braverman
- McGill University Department of Human Genetics and Pediatrics, and The Research Institute of the McGill University Health Centre, Montreal, QC, Canada
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19
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A comprehensive strategy for exome-based preconception carrier screening. Genet Med 2016; 19:583-592. [PMID: 28492530 DOI: 10.1038/gim.2016.153] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/15/2016] [Indexed: 12/14/2022] Open
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20
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Ravenscroft G, Davis MR, Lamont P, Forrest A, Laing NG. New era in genetics of early-onset muscle disease: Breakthroughs and challenges. Semin Cell Dev Biol 2016; 64:160-170. [PMID: 27519468 DOI: 10.1016/j.semcdb.2016.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 08/07/2016] [Accepted: 08/08/2016] [Indexed: 10/21/2022]
Abstract
Early-onset muscle disease includes three major entities that present generally at or before birth: congenital myopathies, congenital muscular dystrophies and congenital myasthenic syndromes. Almost exclusively there is weakness and hypotonia, although cases manifesting hypertonia are increasingly being recognised. These diseases display a wide phenotypic and genetic heterogeneity, with the uptake of next generation sequencing resulting in an unparalleled extension of the phenotype-genotype correlations and "diagnosis by sequencing" due to unbiased sequencing. Perhaps now more than ever, detailed clinical evaluations are necessary to guide the genetic diagnosis; with arrival at a molecular diagnosis frequently occurring following dialogue between the molecular geneticist, the referring clinician and the pathologist. There is an ever-increasing blurring of the boundaries between the congenital myopathies, dystrophies and myasthenic syndromes. In addition, many novel disease genes have been described and new insights have been gained into skeletal muscle development and function. Despite the advances made, a significant percentage of patients remain without a molecular diagnosis, suggesting that there are many more human disease genes and mechanisms to identify. It is now technically- and clinically-feasible to perform next generation sequencing for severe diseases on a population-wide scale, such that preconception-carrier screening can occur. Newborn screening for selected early-onset muscle diseases is also technically and ethically-achievable, with benefits to the patient and family from early management of these diseases and should also be implemented. The need for world-wide Reference Centres to meticulously curate polymorphisms and mutations within a particular gene is becoming increasingly apparent, particularly for interpretation of variants in the large genes which cause early-onset myopathies: NEB, RYR1 and TTN. Functional validation of candidate disease variants is crucial for accurate interpretation of next generation sequencing and appropriate genetic counseling. Many published "pathogenic" variants are too frequent in control populations and are thus likely rare polymorphisms. Mechanisms need to be put in place to systematically update the classification of variants such that accurate interpretation of variants occurs. In this review, we highlight the recent advances made and the challenges ahead for the molecular diagnosis of early-onset muscle diseases.
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Affiliation(s)
- Gianina Ravenscroft
- Harry Perkins Institute of Medical Research and the Centre for Medical Research, University of Western Australia, Nedlands, Australia
| | - Mark R Davis
- Department of Diagnostic Genomics, Pathwest, QEII Medical Centre, Nedlands, Australia
| | - Phillipa Lamont
- Harry Perkins Institute of Medical Research and the Centre for Medical Research, University of Western Australia, Nedlands, Australia; Neurogenetic unit, Dept of Neurology, Royal Perth Hospital and The Perth Children's Hospital, Western Australia, Australia
| | - Alistair Forrest
- Harry Perkins Institute of Medical Research and the Centre for Medical Research, University of Western Australia, Nedlands, Australia
| | - Nigel G Laing
- Harry Perkins Institute of Medical Research and the Centre for Medical Research, University of Western Australia, Nedlands, Australia; Department of Diagnostic Genomics, Pathwest, QEII Medical Centre, Nedlands, Australia.
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21
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Henneman L, Borry P, Chokoshvili D, Cornel MC, van El CG, Forzano F, Hall A, Howard HC, Janssens S, Kayserili H, Lakeman P, Lucassen A, Metcalfe SA, Vidmar L, de Wert G, Dondorp WJ, Peterlin B. Responsible implementation of expanded carrier screening. Eur J Hum Genet 2016; 24:e1-e12. [PMID: 26980105 PMCID: PMC4867464 DOI: 10.1038/ejhg.2015.271] [Citation(s) in RCA: 181] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 11/09/2015] [Accepted: 11/18/2015] [Indexed: 02/07/2023] Open
Abstract
This document of the European Society of Human Genetics contains recommendations regarding responsible implementation of expanded carrier screening. Carrier screening is defined here as the detection of carrier status of recessive diseases in couples or persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Expanded carrier screening offers carrier screening for multiple autosomal and X-linked recessive disorders, facilitated by new genetic testing technologies, and allows testing of individuals regardless of ancestry or geographic origin. Carrier screening aims to identify couples who have an increased risk of having an affected child in order to facilitate informed reproductive decision making. In previous decades, carrier screening was typically performed for one or few relatively common recessive disorders associated with significant morbidity, reduced life-expectancy and often because of a considerable higher carrier frequency in a specific population for certain diseases. New genetic testing technologies enable the expansion of screening to multiple conditions, genes or sequence variants. Expanded carrier screening panels that have been introduced to date have been advertised and offered to health care professionals and the public on a commercial basis. This document discusses the challenges that expanded carrier screening might pose in the context of the lessons learnt from decades of population-based carrier screening and in the context of existing screening criteria. It aims to contribute to the public and professional discussion and to arrive at better clinical and laboratory practice guidelines.
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Affiliation(s)
- Lidewij Henneman
- Department of Clinical Genetics, Section Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Pascal Borry
- Centre for Biomedical Ethics and Law, University of Leuven, Leuven, Belgium
| | - Davit Chokoshvili
- Centre for Biomedical Ethics and Law, University of Leuven, Leuven, Belgium
- Centre for Medical Genetics Ghent, University Hospital Ghent, Ghent, Belgium
| | - Martina C Cornel
- Department of Clinical Genetics, Section Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Carla G van El
- Department of Clinical Genetics, Section Community Genetics and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | | | | | - Heidi C Howard
- Centre for Research Ethics and Bioethics, Uppsala University, Uppsala, Sweden
| | - Sandra Janssens
- Centre for Medical Genetics Ghent, University Hospital Ghent, Ghent, Belgium
| | - Hülya Kayserili
- Department of Medical Genetics, Koç University School of Medicine (KUSoM), Istanbul, Turkey
| | - Phillis Lakeman
- Department of Clinical Genetics, Academic Medical Center, Amsterdam, The Netherlands
| | - Anneke Lucassen
- Department of Clinical Ethics and Law (CELS), University of Southampton and Wessex Clinical Genetic Service, Southampton, UK
| | - Sylvia A Metcalfe
- Murdoch Children's Research Institute and Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
| | - Lovro Vidmar
- Clinical Institute of Medical Genetics, Ljubljana University Medical Centre, Ljubljana, Slovenia
| | - Guido de Wert
- Department of Health, Ethics & Society, Research Schools CAPHRI and GROW, Maastricht University, Maastricht, The Netherlands
| | - Wybo J Dondorp
- Department of Health, Ethics & Society, Research Schools CAPHRI and GROW, Maastricht University, Maastricht, The Netherlands
| | - Borut Peterlin
- Clinical Institute of Medical Genetics, Ljubljana University Medical Centre, Ljubljana, Slovenia
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