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Purpose: Providing feasible preimplantation genetic testing strategies for monogenic disorders (PGT-M) for prevention and control of genetic cancers. Methods: Inclusion of families with a specific pathogenic mutation or a clear family history of genetic cancers. Identification of the distribution of hereditary cancer-related mutations in families through genetic testing. After a series of assisted reproductive measures such as down-regulation, stimulation, egg retrieval, and in vitro fertilization, a biopsy of trophectoderm cells from a blastocyst was performed for single-cell level whole-genome amplification (WGA). Then, the detection of chromosomal aneuploidies was performed by karyomapping. Construction of a haplotype-based linkage analysis to determine whether the embryo carries the mutation. Meanwhile, we performed CNV testing. Finally, embryos can be selected for transfer, and the results will be verified in 18–22 weeks after pregnancy. Results: Six couples with a total of 7 cycles were included in our study. Except for cycle 1 of case 5 which did not result in a transferable embryo, the remaining 6 cycles produced transferable embryos and had a successful pregnancy. Four couples have had amniotic fluid tests to confirm that the fetus does not carry the mutation, while 1 couple was not tested due to insufficient pregnancy weeks. And the remaining couples had to induce labor due to fetal megacystis during pregnancy. Conclusion: Our strategy has been proven to be feasible. It can effectively prevent transmission of hereditary cancer-related mutations to offspring during the prenatal stage. [ABSTRACT FROM AUTHOR]

Purpose: Currently, owing to the limitations of high-throughput sequencing depth and the allele dropout caused by the whole-genome amplification, detection of chromosomal variants in embryos with CNVs <5 Mb is unsatisfactory at the single-cell level using only conventional sequencing methods. Therefore, here we aimed to use a strategy of preimplantation genetic testing for monogenic (PGT-M) to compensate for the shortcomings of conventional sequencing methods. The purpose of this study is to report the effectiveness of haplotype linkage analysis by karyomapping for preimplantation diagnosis microdeletion diseases. Methods: Six couples carrying chromosomal microdeletions associated with X-linked ichthyosis were recruited, and all couples entered the PGT process. Multiple displacement amplification (MDA) method was used to amplify the whole-genome DNA of trophectoderm cells. Then karyomapping based on single nucleotide polymorphism (SNP) was used for haplotype linkage analysis to detect alleles carrying microdeletions, and CNVs of embryos were identified to determine euploid identity. Amniotic fluid tests were performed in the second trimester to verify the PGT-M results. Results: All couples were tested for chromosomal microdeletions, with deletion fragments ranging in size from 1.60 to 1.73 Mb, and one partner in each couple did not carry the microdeletion. Three couples successfully underwent PGT-M assisted conception and obtained healthy live births. Conclusion: This study shows that haplotype linkage analysis by karyomapping could effectively detect the carrier status of embryos with microdeletions at the single-cell level. This approach may be applied to the preimplantation diagnosis of various chromosomal microvariation diseases. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to investigate the relationship between elevated maternal body mass index (BMI) and foetal chromosomal aberrations by performing single-nucleotide polymorphism (SNP) array-based genetic testing on products of conception (POC). Methods: We retrospectively reviewed the data for 1068 assisted reproductive technology (ART)-conceived POC originated from 1068 patients with early spontaneous miscarriage. First, all types of chromosomal abnormalities were defined. Then, the baseline characteristics, including maternal age, BMI, thyroid-stimulating hormone (TSH), gestational age, fertilization method, reasons for fertility treatment, embryo transfer (ET) cycle, stage of embryo development and the embryo morphology grade, were compared between chromosomally normal and abnormal POC groups. Finally, a multivariate logistic regression model was used to analyse various factors affecting the foetal chromosomal abnormality rate. Results: The SNP array results showed that 45.3% (484/1068) of POC were chromosomally normal and that 54.7% (584/1068) of POC presented chromosomal abnormalities. Of these 584 chromosomally abnormal POC, 388 (66.4%) were trisomy, 42 (7.2%) had a monosomy, 68 (11.6%) were found with segmental aneuploidy, 46 (7.9%) were mosaic, 28 (4.8%) were identified as polyploidy and 12 (2.1%) were euploid samples with uniparental disomy (UPD). Multivariate logistic regression results showed that the risk of miscarrying chromosomally abnormal POC increased 1.424-fold in women with normal BMI compared to women with an elevated BMI (≥ 25 kg/m2) (OR = 1.424, 95% CI = 1.074–1.888, p = 0.014). Conclusion: Women with an elevated BMI (≥ 25 kg/m2) are more likely to miscarry chromosomally normal POC. [ABSTRACT FROM AUTHOR]

Purpose: The preimplantation genetic testing for monogenic defects (PGT-M) is a beneficial strategy for the patients suffering from a Mendelian disease, which could protect their offspring from inheriting the disease. The purpose of this study is to report the effectiveness of PGT-M based on karyomapping for three cases of dynamic mutation diseases with trinucleotide repeat expansion. Methods: PGT-M was carried out on three couples, whose family members were diagnosed with Huntington's disease or spinocerebellar ataxias 2 or 12. The whole genome amplification was obtained using the multiple displacement amplification (MDA) method. Then, karyomapping was performed to detect the allele that is carrying the trinucleotide repeat expansion using single nucleotide polymorphism (SNP) linkage analyses, and the copy number variations (CNVs) of the embryos were also identified. Prenatal diagnosis was performed to validate the accuracy of PGT-M. Results: PGT-M was successfully performed on the three couples, and they accepted the transfers of euploid blastocysts without the relevant pathogenic allele. The clinical pregnancies were acquired and the prenatal diagnosis of the three families confirmed the effectiveness of karyomapping. The three born babies were healthy and free of the pathogenic alleles HTT, ATXN2, or PPP2R2B corresponding to Huntington's disease, spinocerebellar ataxias 2 or 12, respectively. Conclusion: This study shows that karyomapping is a highly powerful and efficient approach for dynamic mutation detection in preimplantation embryos. In this work, we first report the birth of healthy babies that are free of the pathogenic gene for dynamic mutation diseases in patients receiving PGT-M by karyomapping. [ABSTRACT FROM AUTHOR]

Purpose: We reviewed the influence of dehydroepiandrosterone (DHEA) supplementation in patients with poor ovarian response (POR) undergoing in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI). Methods: We searched Embase, MEDLINE, PubMed, and the Cochrane Library (1980-2015) for relevant papers and used the Newcastle-Ottawa Scale scoring system to evaluate study quality. Dichotomous data were expressed as pooled relative risk (RR) estimates with fixed or random effect models. Continuous variables were expressed as the weighted mean difference (WMD). All data were analyzed using Revman Software v. 5 and are shown with 95 % confidence intervals (CI). Results: Twenty-one studies met the inclusion criteria. DHEA pretreatment increased the clinical pregnancy rate (RR 1.53, 95 % CI 1.25-1.86), live birth rate (RR 1.87, 95 % CI 1.22-2.88), implantation rate (RR 1.56, 95 % CI 1.20-2.01), and antral follicle count (WMD 0.4, 95 % CI 0.14 to 0.66) while reducing miscarriages (RR 0.50, 95 % CI 0.27-0.90). After subgroup analysis, oocyte numbers and anti-Müllerian hormone levels were also enhanced after DHEA treatment. However, the endometrial thickness and estradiol levels on the day of injecting hCG to induce ovulation were similar between the DHEA supplementation groups and controls. Conclusions: Based on the limited available evidence, DHEA supplementation seems to improve ovarian reserves and IVF/ICSI outcome in patients with POR. Further research is required to clarify the effect of DHEA exposure in assisted reproduction technology. [ABSTRACT FROM AUTHOR]