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Objective: To evaluate the accuracy and diagnostic value of genome-wide noninvasive prenatal testing (NIPT) for the detection of fetal aneuploidies in multiple gestations, with a focus on dichorionic-diamniotic twin pregnancies.Methods: We performed a retrospective cohort study including data from pregnant women with a twin or higher-order gestation who underwent genome-wide NIPT at one of the eight Belgian genetic centers between November 1, 2013, and March 1, 2020. Chorionicity and amnionicity were determined by ultrasonography. Follow-up invasive testing was carried out in the event of positive NIPT results. Sensitivity and specificity were calculated for the detection of trisomy 21, 18, and 13 in the dichorionic-diamniotic twin cohort.Results: Unique NIPT analyses were performed for 4,150 pregnant women with a multiple gestation and an additional 767 with vanishing gestations. The failure rate in multiple gestations excluding vanishing gestations ranged from 0% to 11.7% among the different genetic centers. Overall, the failure rate was 4.8%, which could be reduced to 1.2% after single resampling. There were no common fetal trisomies detected among the 86 monochorionic-monoamniotic and 25 triplet cases. Two monochorionic-diamniotic twins had an NIPT result indicative of a trisomy 21, which was confirmed in both fetuses. Among 2,716 dichorionic-diamniotic twin gestations, a sensitivity of 100% (95% CI 74.12-100%) and a specificity of 100% (95% CI 99.86-100%) was reached for trisomy 21 (n=12). For trisomy 18 (n=3), the respective values were 75% (95% CI 30.06-95.44%) sensitivity and 100% (95% CI 99.86-100%) specificity, and for trisomy 13 (n=2), 100% (95% CI 20.65-100%) sensitivity and 99.96% (95% CI 99.79-99.99%) specificity. In the vanishing gestation group, 28 NIPT results were positive for trisomy 21, 18, or 13, with only five confirmed trisomies.Conclusion: Genome-wide NIPT performed accurately for detection of aneuploidy in dichorionic-diamniotic twin gestations. [ABSTRACT FROM AUTHOR]

Abstract: Background: Thoracic aortic aneurysm/dissection (TAAD) is a common phenotype that may occur as an isolated manifestation or within the constellation of a defined syndrome. In contrast to syndromic TAAD, the elucidation of the genetic basis of isolated TAAD has only recently started. To date, defects have been found in genes encoding extracellular matrix proteins (fibrillin-1, FBN1; collagen type III alpha 1, COL3A1), proteins involved in transforming growth factor beta (TGFβ) signaling (TGFβ receptor 1 and 2, TGFBR1/2; and SMAD3) or proteins that build up the contractile apparatus of aortic smooth muscle cells (myosin heavy chain 11, MYH11; smooth muscle actin alpha 2, ACTA2; and MYLK). Methods and result: In 110 non-syndromic TAAD patients that previously tested negative for FBN1 or TGFBR1/2 mutations, we identified 7 ACTA2 mutations in a cohort of 43 familial TAAD patients, including 2 premature truncating mutations. Sequencing of MYH11 revealed an in frame splice-site alteration in one out of two probands with TAA(D) associated with PDA but none in the series of 22 probands from the cohort of 110 patients with non-syndromic TAAD. Interestingly, immunohistochemical staining of aortic biopsies of a patient and a family member with MYH11 and patients with ACTA2 missense mutations showed upregulation of the TGFβ signaling pathway. Conclusions: MYH11 mutations are rare and typically identified in patients with TAAD associated with PDA. ACTA2 mutations were identified in 16% of a cohort presenting familial TAAD. Different molecular defects in TAAD may account for a different pathogenic mechanism of enhanced TGFβ signaling. [Copyright &y& Elsevier]

Objective: To study the feasibility of in vitro maturation of ovarian tissue oocytes for fertility preservation in transgender men on testosterone treatment.Design: Cross-sectional study SETTING: University hospital PATIENT(S): Eighty-three transgender men enrolled from November 2015 to January 2019 INTERVENTION(S): In vitro maturation of cumulus-oocyte complexes (COCs) harvested at the time of gender confirmation surgery, and fertilization through intracytoplasmic sperm injection.Main Outcome Measure(s): In vitro maturation, fertilization, and blastulation rates; comparison of morphokinetics with vitrified-warmed oocytes; and analysis of the genetic profiles of embryos.Secondary Outcomes: association between serum hormone levels; COCs' morphologic characteristics, and vitrification rate.Result(s): All participants were on testosterone treatment for a median of 83 (64[Quartile 1]; 113.2[Quartile 2]) weeks. A total of 1,903 COCs (mean per participant, 23 ± 15.8) were collected. The in vitro maturation rate was 23.8%, vitrification rate was 21.5%, and survival rate after warming was 72.6% (n = 151). Intracytoplasmic sperm injection was performed in 139 oocytes. The rate of normal fertilized oocytes was 34.5%, and 25 (52.1%) embryos reached day 3. One blastocyst was achieved on day 5. Aberrant cleavage patterns and early embryo arrest were observed in 22 (45.8%) and 44 (91.7%) zygotes, respectively. Compared with vitrified-warmed donor oocytes, a delay was observed in pronuclei disappearance, t2 (time to reach 2 cell stage) timings, and CC1 (the duration of the 1st cell cycle) and SS3 (synchronization of cleavage pattern (calculated as t8-t5) time intervals. A normal genetic pattern was seen in 42% embryos. The proportion of vitrified oocytes was negatively associated with progesterone (odds ratio, 0.76) and positively associated with antimüllerian hormone serum levels (odds ratio, 1.23). The highest vitrification rate was achieved by the morphologic characteristic 344 at day 0 and by 433 at day 2.Conclusion(s): Ovarian tissue oocytes matured in vitro show low developmental capacity in transgender men, when collected under testosterone treatment. [ABSTRACT FROM AUTHOR]

Despite improvements in terms of sequence quality and price per basepair, Sanger sequencing remains restricted to screening of individual disease genes. The development of massively parallel sequencing (MPS) technologies heralded an era in which molecular diagnostics for multigenic disorders becomes reality. Here, we outline different PCR amplification based strategies for the screening of a multitude of genes in a patient cohort. We performed a thorough evaluation in terms of set-up, coverage and sequencing variants on the data of 10 GS-FLX experiments (over 200 patients). Crucially, we determined the actual coverage that is required for reliable diagnostic results using MPS, and provide a tool to calculate the number of patients that can be screened in a single run. Finally, we provide an overview of factors contributing to false negative or false positive mutation calls and suggest ways to maximize sensitivity and specificity, both important in a routine setting. By describing practical strategies for screening of multigenic disorders in a multitude of samples and providing answers to questions about minimum required coverage, the number of patients that can be screened in a single run and the factors that may affect sensitivity and specificity we hope to facilitate the implementation of MPS technology in molecular diagnostics. [ABSTRACT FROM AUTHOR]