1
|
Capalbo A, de Wert G, Mertes H, Klausner L, Coonen E, Spinella F, Van de Velde H, Viville S, Sermon K, Vermeulen N, Lencz T, Carmi S. Screening embryos for polygenic disease risk: a review of epidemiological, clinical, and ethical considerations. Hum Reprod Update 2024:dmae012. [PMID: 38805697 DOI: 10.1093/humupd/dmae012] [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: 01/10/2024] [Revised: 03/25/2024] [Indexed: 05/30/2024] Open
Abstract
BACKGROUND The genetic composition of embryos generated by in vitro fertilization (IVF) can be examined with preimplantation genetic testing (PGT). Until recently, PGT was limited to detecting single-gene, high-risk pathogenic variants, large structural variants, and aneuploidy. Recent advances have made genome-wide genotyping of IVF embryos feasible and affordable, raising the possibility of screening embryos for their risk of polygenic diseases such as breast cancer, hypertension, diabetes, or schizophrenia. Despite a heated debate around this new technology, called polygenic embryo screening (PES; also PGT-P), it is already available to IVF patients in some countries. Several articles have studied epidemiological, clinical, and ethical perspectives on PES; however, a comprehensive, principled review of this emerging field is missing. OBJECTIVE AND RATIONALE This review has four main goals. First, given the interdisciplinary nature of PES studies, we aim to provide a self-contained educational background about PES to reproductive specialists interested in the subject. Second, we provide a comprehensive and critical review of arguments for and against the introduction of PES, crystallizing and prioritizing the key issues. We also cover the attitudes of IVF patients, clinicians, and the public towards PES. Third, we distinguish between possible future groups of PES patients, highlighting the benefits and harms pertaining to each group. Finally, our review, which is supported by ESHRE, is intended to aid healthcare professionals and policymakers in decision-making regarding whether to introduce PES in the clinic, and if so, how, and to whom. SEARCH METHODS We searched for PubMed-indexed articles published between 1/1/2003 and 1/3/2024 using the terms 'polygenic embryo screening', 'polygenic preimplantation', and 'PGT-P'. We limited the review to primary research papers in English whose main focus was PES for medical conditions. We also included papers that did not appear in the search but were deemed relevant. OUTCOMES The main theoretical benefit of PES is a reduction in lifetime polygenic disease risk for children born after screening. The magnitude of the risk reduction has been predicted based on statistical modelling, simulations, and sibling pair analyses. Results based on all methods suggest that under the best-case scenario, large relative risk reductions are possible for one or more diseases. However, as these models abstract several practical limitations, the realized benefits may be smaller, particularly due to a limited number of embryos and unclear future accuracy of the risk estimates. PES may negatively impact patients and their future children, as well as society. The main personal harms are an unindicated IVF treatment, a possible reduction in IVF success rates, and patient confusion, incomplete counselling, and choice overload. The main possible societal harms include discarded embryos, an increasing demand for 'designer babies', overemphasis of the genetic determinants of disease, unequal access, and lower utility in people of non-European ancestries. Benefits and harms will vary across the main potential patient groups, comprising patients already requiring IVF, fertile people with a history of a severe polygenic disease, and fertile healthy people. In the United States, the attitudes of IVF patients and the public towards PES seem positive, while healthcare professionals are cautious, sceptical about clinical utility, and concerned about patient counselling. WIDER IMPLICATIONS The theoretical potential of PES to reduce risk across multiple polygenic diseases requires further research into its benefits and harms. Given the large number of practical limitations and possible harms, particularly unnecessary IVF treatments and discarded viable embryos, PES should be offered only within a research context before further clarity is achieved regarding its balance of benefits and harms. The gap in attitudes between healthcare professionals and the public needs to be narrowed by expanding public and patient education and providing resources for informative and unbiased genetic counselling.
Collapse
Affiliation(s)
- Antonio Capalbo
- Juno Genetics, Department of Reproductive Genetics, Rome, Italy
- Center for Advanced Studies and Technology (CAST), Department of Medical Genetics, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Guido de Wert
- Department of Health, Ethics & Society, CAPHRI-School for Public Health and Primary Care and GROW School for Oncology and Reproduction, Maastricht University, Maastricht, The Netherlands
| | - Heidi Mertes
- Department of Philosophy and Moral Sciences, Ghent University, Ghent, Belgium
- Department of Public Health and Primary Care, Ghent University, Ghent, Belgium
| | - Liraz Klausner
- Braun School of Public Health and Community Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Edith Coonen
- Departments of Clinical Genetics and Reproductive Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
- School for Oncology and Developmental Biology, GROW, Maastricht University, Maastricht, The Netherlands
| | - Francesca Spinella
- Eurofins GENOMA Group Srl, Molecular Genetics Laboratories, Department of Scientific Communication, Rome, Italy
| | - Hilde Van de Velde
- Research Group Genetics Reproduction and Development (GRAD), Vrije Universiteit Brussel, Brussel, Belgium
- Brussels IVF, UZ Brussel, Brussel, Belgium
| | - Stephane Viville
- Laboratoire de Génétique Médicale LGM, Institut de Génétique Médicale d'Alsace IGMA, INSERM UMR 1112, Université de Strasbourg, France
- Laboratoire de Diagnostic Génétique, Unité de Génétique de l'infertilité (UF3472), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Karen Sermon
- Research Group Genetics Reproduction and Development (GRAD), Vrije Universiteit Brussel, Brussel, Belgium
| | | | - Todd Lencz
- Institute of Behavioral Science, Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Departments of Psychiatry and Molecular Medicine, Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Shai Carmi
- Braun School of Public Health and Community Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
2
|
Backenroth D, Altarescu G, Zahdeh F, Mann T, Murik O, Renbaum P, Segel R, Zeligson S, Hakam-Spector E, Carmi S, Zeevi DA. SHaploseek is a sequencing-only, high-resolution method for comprehensive preimplantation genetic testing. Sci Rep 2023; 13:18036. [PMID: 37865712 PMCID: PMC10590366 DOI: 10.1038/s41598-023-45292-z] [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: 06/15/2023] [Accepted: 10/18/2023] [Indexed: 10/23/2023] Open
Abstract
Recent advances in genomic technologies expand the scope and efficiency of preimplantation genetic testing (PGT). We previously developed Haploseek, a clinically-validated, variant-agnostic comprehensive PGT solution. Haploseek is based on microarray genotyping of the embryo's parents and relatives, combined with low-pass sequencing of the embryos. Here, to increase throughput and versatility, we aimed to develop a sequencing-only implementation of Haploseek. Accordingly, we developed SHaploseek, a universal PGT method to determine genome-wide haplotypes of each embryo based on low-pass (≤ 5x) sequencing of the parents and relative(s) along with ultra-low-pass (0.2-0.4x) sequencing of the embryos. We used SHaploseek to analyze five single lymphoblast cells and 31 embryos. We validated the genome-wide haplotype predictions against either bulk DNA, Haploseek, or, at focal genomic sites, PCR-based PGT results. SHaploseek achieved > 99% concordance with bulk DNA in two families from which single cells were derived from grown-up children. In embryos from 12 PGT families, all of SHaploseek's focal site haplotype predictions were concordant with clinical PCR-based PGT results. Genome-wide, there was > 99% median concordance between Haploseek and SHaploseek's haplotype predictions. Concordance remained high at all assayed sequencing depths ≥ 2x, as well as with only 1ng of parental DNA input. In subtelomeric regions, significantly more haplotype predictions were high-confidence in SHaploseek compared to Haploseek. In summary, SHaploseek constitutes a single-platform, accurate, and cost-effective comprehensive PGT solution.
Collapse
Affiliation(s)
- Daniel Backenroth
- Braun School of Public Health and Community Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Gheona Altarescu
- PGT Unit, Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
- Faculty of Medicine, Hebrew University, Jerusalem, Israel
| | - Fouad Zahdeh
- Translational Genomics Lab, Medical Genetics Institute, Shaare Zedek Medical Center, Bayit Str. 12, P.O.Box 3235, 91031, Jerusalem, Israel
| | - Tzvia Mann
- Translational Genomics Lab, Medical Genetics Institute, Shaare Zedek Medical Center, Bayit Str. 12, P.O.Box 3235, 91031, Jerusalem, Israel
| | - Omer Murik
- Translational Genomics Lab, Medical Genetics Institute, Shaare Zedek Medical Center, Bayit Str. 12, P.O.Box 3235, 91031, Jerusalem, Israel
| | - Paul Renbaum
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Reeval Segel
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Sharon Zeligson
- Medical Genetics Institute, Shaare Zedek Medical Center, Jerusalem, Israel
| | | | - Shai Carmi
- Braun School of Public Health and Community Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - David A Zeevi
- Translational Genomics Lab, Medical Genetics Institute, Shaare Zedek Medical Center, Bayit Str. 12, P.O.Box 3235, 91031, Jerusalem, Israel.
| |
Collapse
|
3
|
Horer S, Feichtinger M, Rosner M, Hengstschläger M. Pluripotent Stem Cell-Derived In Vitro Gametogenesis and Synthetic Embryos-It Is Never Too Early for an Ethical Debate. Stem Cells Transl Med 2023; 12:569-575. [PMID: 37471266 PMCID: PMC10502567 DOI: 10.1093/stcltm/szad042] [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: 03/23/2023] [Accepted: 06/23/2023] [Indexed: 07/22/2023] Open
Abstract
Recently, 2 branches of the wide area of synthetic biology-in vitro gametogenesis and synthetic embryo development-have gained considerable attention. Rodent induced pluripotent stem cells derived via reprogramming of somatic cells can in vitro be differentiated into gametes to produce fertile offspring. And even synthetic embryos with organ progenitors were generated ex utero entirely from murine pluripotent stem cells. The use of these approaches in basic research, which is rightfully accompanied by an ethical discussion, will allow hitherto unattainable insights into the processes of the beginning of life. There is a broad international consensus that currently the application of these technologies in human-assisted reproduction must be considered to be unsafe and unethical. However, newspaper headlines also addressed the putatively resulting paradigm shift in human reproduction and thereby raised expectations in patients. Due to unsolved biological and technological obstacles, most scientists do not anticipate translation of any of these approaches into human reproductive medicine, if ever, for the next 10 years. Still, whereas the usage of synthetic embryos for reproductive purposes should be banned, in the context of in vitro-derived human gametes it is not too early to initiate the evaluation of the ethical implications, which could still remain assuming all technological hurdles can ever be cleared.
Collapse
Affiliation(s)
- Stefanie Horer
- Institute of Medical Genetics, Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | | | - Margit Rosner
- Institute of Medical Genetics, Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Markus Hengstschläger
- Institute of Medical Genetics, Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
4
|
Nguyen XTA, Moekotte L, Plomp AS, Bergen AA, van Genderen MM, Boon CJF. Retinitis Pigmentosa: Current Clinical Management and Emerging Therapies. Int J Mol Sci 2023; 24:ijms24087481. [PMID: 37108642 PMCID: PMC10139437 DOI: 10.3390/ijms24087481] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/01/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
Retinitis pigmentosa (RP) comprises a group of inherited retinal dystrophies characterized by the degeneration of rod photoreceptors, followed by the degeneration of cone photoreceptors. As a result of photoreceptor degeneration, affected individuals experience gradual loss of visual function, with primary symptoms of progressive nyctalopia, constricted visual fields and, ultimately, central vision loss. The onset, severity and clinical course of RP shows great variability and unpredictability, with most patients already experiencing some degree of visual disability in childhood. While RP is currently untreatable for the majority of patients, significant efforts have been made in the development of genetic therapies, which offer new hope for treatment for patients affected by inherited retinal dystrophies. In this exciting era of emerging gene therapies, it remains imperative to continue supporting patients with RP using all available options to manage their condition. Patients with RP experience a wide variety of physical, mental and social-emotional difficulties during their lifetime, of which some require timely intervention. This review aims to familiarize readers with clinical management options that are currently available for patients with RP.
Collapse
Affiliation(s)
- Xuan-Thanh-An Nguyen
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Lude Moekotte
- Department of Ophthalmology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Astrid S Plomp
- Department of Clinical Genetics, Amsterdam University Medical Centers, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Arthur A Bergen
- Department of Clinical Genetics, Amsterdam University Medical Centers, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Maria M van Genderen
- Department of Ophthalmology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
- Bartiméus, Diagnostic Center for Complex Visual Disorders, 3703 AJ Zeist, The Netherlands
| | - Camiel J F Boon
- Department of Ophthalmology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
- Department of Ophthalmology, Amsterdam University Medical Centers, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| |
Collapse
|
5
|
Kumar A, Im K, Banjevic M, Ng PC, Tunstall T, Garcia G, Galhardo L, Sun J, Schaedel ON, Levy B, Hongo D, Kijacic D, Kiehl M, Tran ND, Klatsky PC, Rabinowitz M. Whole-genome risk prediction of common diseases in human preimplantation embryos. Nat Med 2022; 28:513-516. [PMID: 35314819 PMCID: PMC8938270 DOI: 10.1038/s41591-022-01735-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 02/04/2022] [Indexed: 12/14/2022]
Abstract
Preimplantation genetic testing (PGT) of in-vitro-fertilized embryos has been proposed as a method to reduce transmission of common disease; however, more comprehensive embryo genetic assessment, combining the effects of common variants and rare variants, remains unavailable. Here, we used a combination of molecular and statistical techniques to reliably infer inherited genome sequence in 110 embryos and model susceptibility across 12 common conditions. We observed a genotype accuracy of 99.0–99.4% at sites relevant to polygenic risk scoring in cases from day-5 embryo biopsies and 97.2–99.1% in cases from day-3 embryo biopsies. Combining rare variants with polygenic risk score (PRS) magnifies predicted differences across sibling embryos. For example, in a couple with a pathogenic BRCA1 variant, we predicted a 15-fold difference in odds ratio (OR) across siblings when combining versus a 4.5-fold or 3-fold difference with BRCA1 or PRS alone. Our findings may inform the discussion of utility and implementation of genome-based PGT in clinical practice. A computational approach combining whole-genome sequencing of parental genomes and genotyping of preimplantation embryos allows accurate prediction of the inherited genomes of embryos and calculation of polygenic risk scores.
Collapse
Affiliation(s)
| | - Kate Im
- MyOme, Inc., Menlo Park, CA, USA
| | | | | | | | | | | | | | | | - Brynn Levy
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | | | | | | | - Nam D Tran
- Spring Fertility, San Francisco, CA, USA
| | | | | |
Collapse
|
6
|
Yanagimachi R. Mysteries and unsolved problems of mammalian fertilization and related topics. Biol Reprod 2022; 106:644-675. [PMID: 35292804 PMCID: PMC9040664 DOI: 10.1093/biolre/ioac037] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 02/10/2022] [Accepted: 02/10/2022] [Indexed: 11/13/2022] Open
Abstract
Mammalian fertilization is a fascinating process that leads to the formation of a new individual. Eggs and sperm are complex cells that must meet at the appropriate time and position within the female reproductive tract for successful fertilization. I have been studying various aspects of mammalian fertilization over 60 years. In this review, I discuss many different aspects of mammalian fertilization, some of my laboratory's contribution to the field, and discuss enigmas and mysteries that remain to be solved.
Collapse
Affiliation(s)
- Ryuzo Yanagimachi
- Institute for Biogenesis Research, University of Hawaii Medical School, Honolulu, Hawaii, USA
| |
Collapse
|
7
|
Rogers A, Menezes M, Kane SC, Zander-Fox D, Hardy T. Preimplantation Genetic Testing for Monogenic Conditions: Is Cell-Free DNA Testing the Next Step? Mol Diagn Ther 2021; 25:683-690. [PMID: 34495483 DOI: 10.1007/s40291-021-00556-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 11/25/2022]
Abstract
Genetic assessment of an embryo via preimplantation genetic testing (PGT) represents an important reproductive option for couples wanting to try and improve success rates from in vitro fertilisation (IVF) cycles, as well as reduce their risk of having a child born with a genetic condition. Currently, biopsy of the developing embryo prior to transfer allows genetic assessment of an embryo for either chromosome copy number (aneuploidy [PGT-A] or segmental rearrangement [PGT-SR]) or to avoid the transmission of a single gene condition (monogenic conditions [PGT-M]). However, this technology is invasive and commands considerable resources. Non-invasive PGT (niPGT) offers a potential alternate mode of embryonic analysis. Whilst the utility of niPGT-A has been recently explored, there has been limited consideration of niPGT-M as an option for couples at risk of passing on a single gene or chromosomal condition. This review examines the historical and current clinical context of preimplantation embryonic analysis for monogenic conditions, in addition to important considerations surrounding the origin and analysis of cell-free deoxyribose nucleic acid (cfDNA), whether it is sourced via blastocentesis or spent embryonic culture medium (SCM). Future capabilities of this testing modality will almost certainly be enhanced by integration of whole genome sequencing into everyday practice. In addition, the increased utilisation of reproductive carrier screening as part of standard reproductive healthcare will likely result in the identification of a larger high-risk population. As a result, stratification of limited and highly specialised reproductive genetic resources will be required. Prospective parents should continue to be made aware of the limitations of this technology, with prenatal confirmatory testing remaining an essential part of antenatal care in these patients. However, niPGT-M poses an important alternate testing modality for high-risk couples, particularly in the setting of embryos that cannot be biopsied for traditional PGT-M and as demand for this treatment continues to grow.
Collapse
Affiliation(s)
- Alice Rogers
- Genetics, Repromed, Monash IVF, 180 Fullarton Road, Dulwich, SA, 5065, Australia
| | - Melody Menezes
- Monash Ultrasound for Women, Richmond, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
| | - Stefan C Kane
- Monash Ultrasound for Women, Richmond, VIC, Australia
- Department of Obstetrics and Gynaecology, The University of Melbourne, Parkville, VIC, Australia
- Department of Maternal Fetal Medicine, The Royal Women's Hospital, Parkville, VIC, Australia
| | - Deirdre Zander-Fox
- Monash IVF Group, Clayton, VIC, Australia
- Monash University, Clayton, VIC, Australia
- The University of Adelaide, Adelaide, SA, Australia
- University of South Australia, Adelaide, SA, Australia
| | - Tristan Hardy
- Genetics, Repromed, Monash IVF, 180 Fullarton Road, Dulwich, SA, 5065, Australia.
- Genetics and Molecular Pathology, SA Pathology, Adelaide, Australia.
| |
Collapse
|
8
|
Blyth U, Craciunas L, Hudson G, Choudhary M. Maternal germline factors associated with aneuploid pregnancy loss: a systematic review. Hum Reprod Update 2021; 27:866-884. [PMID: 33969392 DOI: 10.1093/humupd/dmab010] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 03/02/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Miscarriage describes the spontaneous loss of pregnancy before the threshold of viability; the vast majority occur before 12 weeks of gestation. Miscarriage affects one in four couples and is the most common complication of pregnancy. Chromosomal abnormalities of the embryo are identified in ∼50% of first trimester miscarriages; aneuploidy accounts for 86% of these cases. The majority of trisomic miscarriages are of maternal origin with errors occurring during meiotic division of the oocytes. Chromosome segregation errors in oocytes may be sporadic events secondary to advancing maternal age; however, there is increasing evidence to suggest possible maternal germline contributions to this. OBJECTIVE AND RATIONALE The objective of this review was to appraise critically the existing evidence relating to maternal germline factors associated with pregnancy loss secondary to embryo aneuploidy, identify limitations in the current evidence base and establish areas requiring further research. SEARCH METHODS The initial literature search was performed in September 2019 and updated in January 2021 using the electronic databases OVID MEDLINE, EMBASE and the Cochrane Library. No time or language restrictions were applied to the searches and only primary research was included. Participants were women who had suffered pregnancy loss secondary to numerical chromosomal abnormalities of the embryo. Study identification and subsequent data extraction were performed by two authors independently. The Newcastle-Ottawa Scale was used to judge the quality of the included studies. The results were synthesized narratively. OUTCOMES The literature search identified 2198 titles once duplicates were removed, of which 21 were eligible for inclusion in this systematic review. They reported on maternal germline factors having variable degrees of association with pregnancy loss of aneuploid origin. The Online Mendelian Inheritance in Man (OMIM) gene ontology database was used as a reference to establish the functional role currently attributed to the genes reported. The majority of the cases reported and included were secondary to the inheritance of maternal structural factors such as Robertsonian translocations, deletions and insertions. Germline factors with a plausible role in aneuploid pregnancy loss of maternal origin included skewed X-inactivation and CGG repeats in the fragile X mental retardation (FMR1) gene. Studies that reported the association of single gene mutations with aneuploid pregnancy loss were conflicting. Single gene mutations with an uncertain or no role in aneuploid pregnancy loss included mutations in synaptonemal complex protein 3 (SYCP3), mitotic polo-like kinase 4 (PLK4) and meiotic stromal antigen 3 (STAG3) spindle integrity variants and 5,10-methylenetetrahydrofolate reductase (MTHFR). WIDER IMPLICATIONS Identifying maternal genetic factors associated with an increased risk of aneuploidy will expand our understanding of cell division, non-disjunction and miscarriage secondary to embryo aneuploidy. The candidate germline factors identified may be incorporated in a screening panel for women suffering miscarriage of aneuploidy aetiology to facilitate counselling for subsequent pregnancies.
Collapse
Affiliation(s)
- Ursula Blyth
- Newcastle Fertility Centre at Life, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Laurentiu Craciunas
- Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Gavin Hudson
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Meenakshi Choudhary
- Newcastle Fertility Centre at Life, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| |
Collapse
|
9
|
Expanded clinical validation of Haploseek for comprehensive preimplantation genetic testing. Genet Med 2021; 23:1334-1340. [PMID: 33772222 DOI: 10.1038/s41436-021-01145-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 11/08/2022] Open
Abstract
PURPOSE We previously developed Haploseek, a method for comprehensive preimplantation genetic testing (PGT). However, some key features were missing, and the method has not yet been systematically validated. METHODS We extended Haploseek to incorporate DNA from embryo grandparents and to allow testing of variants on chromosome X or in regions where parents share common haplotypes. We then validated Haploseek on 151 embryo biopsies from 27 clinical PGT cases. We sequenced all biopsies to low coverage (0.2×), and performed single-nucleotide polymorphism (SNP) microarray genotyping on the embryos' parents and siblings/grandparents. We used the extended Haploseek to predict chromosome copy-number variants (CNVs) and relevant variant-flanking haplotypes in each embryo. We validated haplotype predictions for each clinical sample against polymerase chain reaction (PCR)-based PGT case results, and CNV predictions against established commercial kits. RESULTS For each of the 151 embryo biopsies, all Haploseek-derived haplotypes and CNVs were concordant with clinical PGT results. The cases included 17 autosomal dominant, 5 autosomal recessive, and 3 X-linked monogenic disorders. In addition, we evaluated 1 Robertsonian and 2 reciprocal translocations, and 17 cases of chromosome copy-number counting were performed. CONCLUSION Our results demonstrate that Haploseek is clinically accurate and fit for all standard clinical PGT applications.
Collapse
|
10
|
Coticchio G, Behr B, Campbell A, Meseguer M, Morbeck DE, Pisaturo V, Plancha CE, Sakkas D, Xu Y, D'Hooghe T, Cottell E, Lundin K. Fertility technologies and how to optimize laboratory performance to support the shortening of time to birth of a healthy singleton: a Delphi consensus. J Assist Reprod Genet 2021; 38:1021-1043. [PMID: 33599923 DOI: 10.1007/s10815-021-02077-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/18/2021] [Indexed: 12/13/2022] Open
Abstract
PURPOSE To explore how the assisted reproductive technology (ART) laboratories can be optimized and standardized to enhance embryo culture and selection, to bridge the gap between standard practice and the new concept of shortening time to healthy singleton birth. METHODS A Delphi consensus was conducted (January to July 2018) to assess how the ART laboratory could be optimized, in conjunction with existing guidelines, to reduce the time to a healthy singleton birth. Eight experts plus the coordinator discussed and refined statements proposed by the coordinator. The statements were distributed via an online survey to 29 participants (including the eight experts from step 1), who voted on their agreement/disagreement with each statement. Consensus was reached if ≥ 66% of participants agreed/disagreed with a statement. If consensus was not achieved for any statement, that statement was revised and the process repeated until consensus was achieved. Details of statements achieving consensus were communicated to the participants. RESULTS Consensus was achieved for all 13 statements, which underlined the need for professional guidelines and standardization of lab processes to increase laboratory competency and quality. The most important points identified were the improvement of embryo culture and embryo assessment to shorten time to live birth through the availability of more high-quality embryos, priority selection of the most viable embryos and improved cryosurvival. CONCLUSION The efficiency of the ART laboratory can be improved through professional guidelines on standardized practices and optimized embryo culture environment, assessment, selection and cryopreservation methodologies, thereby reducing the time to a healthy singleton delivery.
Collapse
Affiliation(s)
- Giovanni Coticchio
- 9.baby Family and Fertility Center, Via Dante, 15, 40125, Bologna, Italy.
| | - Barry Behr
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics & Gynecology, Stanford University School of Medicine, Stanford, CA, USA
| | | | | | - Dean E Morbeck
- Fertility Associates, Auckland, New Zealand
- Department of Obstetrics and Gynaecology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Valerio Pisaturo
- Reproductive Medicine Department, International Evangelical Hospital, Genoa, Italy
| | - Carlos E Plancha
- Inst. Histologia e Biologia do Desenvolvimento, Faculdade de Medicina, Universidade de Lisboa and CEMEARE, Lisbon, Portugal
| | - Denny Sakkas
- Boston IVF, Waltham, MA, USA
- Department of Obstetrics and Gynecology, Yale University, New Haven, CT, USA
| | - Yanwen Xu
- Reproductive Medicine Center, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Thomas D'Hooghe
- Department of Obstetrics and Gynecology, Yale University, New Haven, CT, USA
- Global Medical Affairs Fertility, R&D Biopharma, Merck KGaA, Darmstadt, Germany
- Department of Development and Regeneration, Biomedical Sciences Group, KU Leuven (University of Leuven), Leuven, Belgium
| | - Evelyn Cottell
- Global Medical Affairs Fertility, R&D Biopharma, Merck KGaA, Darmstadt, Germany
| | - Kersti Lundin
- Reproductive Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| |
Collapse
|
11
|
Preimplantation Genetic Testing for Chromosomal Abnormalities: Aneuploidy, Mosaicism, and Structural Rearrangements. Genes (Basel) 2020; 11:genes11060602. [PMID: 32485954 PMCID: PMC7349251 DOI: 10.3390/genes11060602] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 12/18/2022] Open
Abstract
There is a high incidence of chromosomal abnormalities in early human embryos, whether they are generated by natural conception or by assisted reproductive technologies (ART). Cells with chromosomal copy number deviations or chromosome structural rearrangements can compromise the viability of embryos; much of the naturally low human fecundity as well as low success rates of ART can be ascribed to these cytogenetic defects. Chromosomal anomalies are also responsible for a large proportion of miscarriages and congenital disorders. There is therefore tremendous value in methods that identify embryos containing chromosomal abnormalities before intrauterine transfer to a patient being treated for infertility—the goal being the exclusion of affected embryos in order to improve clinical outcomes. This is the rationale behind preimplantation genetic testing for aneuploidy (PGT-A) and structural rearrangements (-SR). Contemporary methods are capable of much more than detecting whole chromosome abnormalities (e.g., monosomy/trisomy). Technical enhancements and increased resolution and sensitivity permit the identification of chromosomal mosaicism (embryos containing a mix of normal and abnormal cells), as well as the detection of sub-chromosomal abnormalities such as segmental deletions and duplications. Earlier approaches to screening for chromosomal abnormalities yielded a binary result of normal versus abnormal, but the new refinements in the system call for new categories, each with specific clinical outcomes and nuances for clinical management. This review intends to give an overview of PGT-A and -SR, emphasizing recent advances and areas of active development.
Collapse
|