Project description: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.
Project description:Uterus transplantation is an emerging treatment for uterine factor infertility. In vitro fertilization with cryopreservation of embryos prior is required before a patient can be listed for transplant. Whether or not to perform universal preimplantation genetic testing for aneuploidy should be addressed by centers considering a uterus transplant program. The advantages and disadvantages of preimplantation genetic testing for aneuploidy in this unique population are presented. The available literature is reviewed to determine the utility of preimplantation genetic testing for aneuploidy in uterus transplantation protocols. Theoretical benefits of preimplantation genetic testing for aneuploidy include decreased time to pregnancy in a population that benefits from minimization of exposure to immunosuppressive agents and decreased chance of spontaneous abortion requiring a dilation and curettage. Drawbacks include increased cost per in vitro fertilization cycle, increased number of required in vitro fertilization cycles to achieve a suitable number of embryos prior to listing for transplant, and a questionable benefit to live birth rate in younger patients. Thoughtful consideration of whether or not to use preimplantation genetic testing for aneuploidy is necessary in uterus transplant trials. Age is likely a primary factor that can be useful in determining which uterus transplant recipients benefit from preimplantation genetic testing for aneuploidy.
Project description:PurposeThe purpose of this study is to summarize the clinical outcomes of apparently balanced chromosome rearrangement (ABCR) carriers in preimplantation genetic testing (PGT) cycles by next-generation sequencing following microdissecting junction region (MicroSeq) to distinguish non-carrier embryos from balanced carriers.MethodsA retrospective study of 762 ABCR carrier couples who requested PGT for structural rearrangements combined with MicroSeq at the Reproductive and Genetic Hospital of CITIC-Xiangya was conducted between October 2014 and October 2019.ResultsTrophectoderm biopsy was performed in 4122 blastocysts derived from 917 PGT-SR cycles and 3781 blastocysts were detected. Among the 3781 blastocysts diagnosed, 1433 (37.9%, 1433/3781) were balanced, of which 739 blastocysts were carriers (51.57%, 739/1433) and 694 blastocysts were normal (48.43%, 694/1433). Approximately 26.39% of cycles had both carrier and normal embryo transfer, and the average number of biopsied blastocysts was 6.7. In the cumulative 223 biopsied cycles with normal embryo transfer, all couples chose to transfer the normal embryos. In the 225 cycles with only carrier embryos, the couples chose to transfer the carrier embryos in 169/225 (75.11%) cycles. A total of 732 frozen embryo transfer cycles were performed, resulting in 502 clinical pregnancies. Cumulatively, 326 babies were born; all of these babies were healthy and free of any developmental issues.ConclusionOur study provides the first evaluation of the clinical outcomes of a large sample with ABCR carrier couples undergoing the MicroSeq-PGT technique and reveals its powerful ability to distinguish between carrier and non-carrier balanced embryos.
Project description:BACKGROUND:Preimplantation genetic testing (PGT) is widely used today in in-vitro fertilization (IVF) centers over the world for selecting euploid embryos for transfer and to improve clinical outcomes in terms of embryo implantation, clinical pregnancy, and live birth rates. METHODS:We report the current knowledge concerning these procedures and the results from different clinical indications in which PGT is commonly applied. RESULTS:This paper illustrates different molecular techniques used for this purpose and the clinical significance of the different oocyte and embryo stage (polar bodies, cleavage embryo, and blastocyst) at which it is possible to perform sampling biopsies for PGT. Finally, genetic origin and clinical significance of embryo mosaicism are illustrated. CONCLUSIONS:The preimplantation genetic testing is a valid technique to evaluated embryo euploidy and mosaicism before transfer.
Project description:Background and objectivesA genetic cause can be identified for an increasing number of pediatric and adult-onset kidney diseases. Preimplantation genetic testing (formerly known as preimplantation genetic diagnostics) is a reproductive technology that helps prospective parents to prevent passing on (a) disease-causing mutation(s) to their offspring. Here, we provide a clinical overview of 25 years of preimplantation genetic testing for monogenic kidney disease in The Netherlands.Design, setting, participants, & measurementsThis is a retrospective cohort study of couples counseled on preimplantation genetic testing for monogenic kidney disease in the national preimplantation genetic testing expert center (Maastricht University Medical Center+) from January 1995 to June 2019. Statistical analysis was performed through chi-squared tests.ResultsIn total, 98 couples were counseled regarding preimplantation genetic testing, of whom 53% opted for preimplantation genetic testing. The most frequent indications for referral were autosomal dominant polycystic kidney disease (38%), Alport syndrome (26%), and autosomal recessive polycystic kidney disease (9%). Of couples with at least one preimplantation genetic testing cycle with oocyte retrieval, 65% experienced one or more live births of an unaffected child. Of couples counseled, 38% declined preimplantation genetic testing for various personal and technical reasons.ConclusionsReferrals, including for adult-onset disease, have increased steadily over the past decade. Though some couples decline preimplantation genetic testing, in the couples who proceed with at least one preimplantation genetic testing cycle, almost two thirds experienced at least one live birth rate.
Project description:PurposeTo evaluate the use of preimplantation genetic testing (PGT) and live birth rates (LBR) in the USA from 2014 to 2017 and to understand how PGT is being used at a clinic and state level.MethodsThis study accessed SART data for 2014 to 2017 to determine LBR and the CDC for years 2016 and 2017 to identify PGT usage. Primary cycles included only the first embryo transfer within 1 year of an oocyte retrieval; subsequent cycles included transfers occurring after the first transfer or beyond 1 year of oocyte retrieval.ResultsIn the SART data, the number of primary PGT cycles showed a significant monotonic annual increase from 18,805 in 2014 to 54,442 in 2017 (P = 0.042) and subsequent PGT cycles in these years increased from 2946 to 14,361 (P = 0.01). There was a significant difference in primary PGT cycle use by age, where younger women had a greater percentage of PGT treatment cycles than older women. In both PGT and non-PGT cycles, the LBR per oocyte retrieval decreased significantly from 2014 to 2017 (P<0001) and younger women had a significantly higher LBR per oocyte retrieval compared to older women (P < 0.001). The CDC data revealed that in 2016, just 53 (11.4%) clinics used PGT for more than 50% of their cycles, which increased to 99 (21.4%) clinics in 2017 (P< 0.001).ConclusionsA growing number of US clinics are offering PGT to their patients. These findings support re-evaluation of the application for PGT.
Project description:PurposeTo study the application of next-generation sequencing on preimplantation genetic testing for recurrent hydatidiform mole patients.MethodsA total of ten recurrent hydatidiform mole patients aged 27-34 years with a history of at least twice hydatidiform moles and no normal pregnancy were collected from 2019 to 2020. The diagnosis of hydatidiform mole type was clarified using short tandem repeat genotyping on products of conception, and whole-exome sequencing was applied for all patients and their partners. Seven recurrent hydatidiform mole patients with complete hydatidiform mole/partial hydatidiform mole type among previous hydatidiform mole tissues and no Pathogenetic/Likely pathogenetic/Uncertain significance variants in NLRP7/KHDC3L/MEI1/C11orf80 underwent a procedure of preimplantation genetic testing. Next-generation sequencing for analyzing the copy number variants and the numbers of heterozygous single nucleotide polymorphism was adopted to clarify the ploidy and parental origin of the embryo chromosomes in vitro. Embryos with biparental diploidy were selected for transfer.ResultsSeven patients have undergone the procedure of preimplantation genetic testing, and twenty-three embryos were obtained, among which 82.6% (n = 19) were identified transferrable and 17.4% (n = 4) were identified aneuploid. Two patients have delivered healthy babies and another is currently in the second trimester after transfer.ConclusionAnalyzing the copy number variants and the numbers of heterozygous single nucleotide polymorphism on the basis of next-generation sequencing can be utilized in the procedure of preimplantation genetic testing among part of recurrent hydatidiform mole patients. The current study is effective to reduce the occurrence of hydatidiform mole with improved clinical strategy, the advanced testing technology and analysis methods, as three of seven patients have conceived or delivered successfully.
Project description:PurposeThis study aimed to evaluate the rates of euploidy, aneuploidy, and mosaicism in preimplantation genetic testing for structural rearrangements (PGT-SR) cycles from chromosomal inversion carriers. In addition, this work also focused on assessing the impact of some contributors on the incidence of parental originating aneuploidy and mosaicism.MethodsThis retrospective review enrolled chromosomal inversion carrier couples of whom the females were under 38 years old undergoing PGT-SR at a single academic reproductive center. Subgroups were divided according to the gender of carriers, the inversion type, and the semen parameters of male carriers (male factor infertility (MF) or non-MF). Patient demographics, cycle characteristics, and PGT-SR outcomes were compared among subgroups.ResultsA total of 71 PGT-SR cycles from 57 inversion carrier couples were included for analysis. Among the 283 blastocysts, 48.4% were identified as euploidy, 27.9% as aneuploidy, and the remaining 23.7% as mosaicism. Only 32.9% of aneuploid embryos and 1.5% of mosaic embryos involved the parental inversion chromosomes. Notably, the female inversion carriers seemed to produce more parental originating aneuploid embryos than male inversion carriers (45.5% vs 23.9%, p = 0.044).ConclusionsThe type of inversion and sperm parameters of male chromosomal inversion carriers did not affect the ploidy status of embryos. The incidence of parental originating aneuploidy in inversion carrier couples is lower than expected. For male chromosomal inversion carriers with normal sperm condition whose female partners are under 38 years old, natural conception combined with prenatal diagnosis could be provided as an option during fertility counseling.
Project description:Background Previous studies suggested that non-invasive preimplantation genetic testing (niPGT) for intracytoplasmic sperm injection (ICSI) blastocysts can be used to identify chromosomal ploidy and chromosomal abnormalities. Here, we report the feasibility and performance of niPGT for conventional in vitro fertilization (IVF) blastocysts. Methods This was a prospective observational study. In the preclinical stage, whole genome amplification and NGS were performed using the sperm spent culture medium (SCM). Then, trophectoderm (TE) biopsies and corresponding SCM derived from 27 conventional IVF monopronuclear embryos were collected. In the clinical stage, samples from 25 conventional IVF cycles and 37 ICSI cycles from April 2020–August 2021 were collected for performance evaluation. Results Preclinically, we confirmed failed sperm DNA amplification under the current amplification system. Subsequent niPGT from the 27 monopronuclear blastocysts showed 69.2% concordance with PGT results of corresponding TE biopsies. In the clinical stage, no paternal contamination was observed in any of the 161 SCM samples from conventional IVF. While maternal contamination was observed in 29.8% (48/161) SCM samples, only 2.5% (4/161) samples had a contamination ratio ≥ 50%. Compared with that of TE biopsy, the performances of NiPGT from 161 conventional IVF embryos and 122 ICSI embryos were not significantly different (P > 0.05), with ploidy concordance rates of 75% and 74.6% for IVF and ICSI methods, respectively. Finally, evaluation of the euploid probability of embryos with different types of niPGT results showed prediction probabilities of 82.8%, 77.8%, 62.5%, 50.0%, 40.9% and 18.4% for euploidy, sex-chromosome mosaics only, low-level mosaics, multiple abnormal chromosomes, high-level mosaics and aneuploidy, respectively. Conclusions Our research results preliminarily confirm that the niPGT approach using SCM from conventional IVF has comparable performance with ICSI and might broadening the application scope of niPGT. Supplementary Information The online version contains supplementary material available at 10.1186/s12967-022-03596-0.
Project description:ObjectiveNoninvasive prenatal testing (NIPT) is widely used in clinical detection of fetal autosomal duplications or deletions. The aim of this study was to investigate the clinical application of NIPT for detection of chromosomal microdeletions.MethodsMicrodeletions of about 5 Mb in the long arm of chromosome 15 (q11.2-q12) were detected by NIPT and were confirmed by karyotype analysis and copy number variation (CNV) analysis based on high-throughput sequencing technology.ResultsThe CNV results of prenatal diagnosis showed that there were approximately 4.96 Mb of microdeletions in 15q11.2-q13.1, which was consistent with the NIPT results. The karyotype analysis showed no abnormalities.ConclusionIn this study, the microdeletion fragment of fetal chromosome 15 was successfully detected and diagnosed using NIPT. This suggests that NIPT is an efficient method to gain genetic information about chromosomal abnormalities.