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Aims: The aim was to evaluate whether assisted reproductive technology (ART) affects the development of the fetal central nervous system (CNS). Methods: This study was carried out on women with singleton pregnancies, including 427 women who became pregnant by ART and 32,859 women with natural conceptions (NCs). The cavum septum pellucidum (CSP) width, transverse cerebellar diameter (TCD), cisterna magna (CM) depth, and lateral ventricle width were measured by ultrasound for 72 normal ART fetuses and 201 normal NC fetuses. The malformation rate of CNS was determined for both groups. Results: In both groups, significant positive correlations with gestational age were found for CSP width (ART: r=0.7841, NC: r=0.7864; P<0.0001) and for TCD (ART: r=0.7698, NC: r=0.6926; P<0.0001). However, neither CM depth nor lateral ventricle width showed a significant correlation with gestational age. None of the measured parameters showed a statistically significant difference between the two groups. The CNS malformation detection rate was 1.2% (5/427) in ART fetuses and 0.9% (296/32,859) in NC fetuses. It did not reach statistical significance (P>0.05). Conclusions: The development and malformation rate of the fetal CNS is not significantly different between ART and NC fetuses, thus, ART does not affect the development of the fetal brain. [ABSTRACT FROM AUTHOR]

Presents information on a study of inherited mutations in the BRCA1 gene among Chinese patients with breast cancer. Information on the BRCA1 tumor suppressor gene; Methodology; Information on the four BRCA1 mutations that recur in Oriental populations; Other prevalent mutations.

Objectives: The predisposition of intracranial atherosclerotic disease (ICAD) to East Asians over Caucasians infers a genetic basis which, however, remains largely unknown. Higher prevalence of vascular risk factors (VRFs) in Chinese over Caucasian patients who had a stroke, and shared risk factors of ICAD with other stroke subtypes indicate genes related to VRFs and/or other stroke subtypes may also contribute to ICAD., Methods: Unrelated symptomatic patients with ICAD were recruited for genome sequencing (GS, 60-fold). Rare and potentially deleterious single-nucleotide variants (SNVs) and small insertions/deletions (InDels) were detected in genome-wide and correlated to genes related to VRFs and/or other stroke subtypes. Rare aneuploidies, copy number variants (CNVs) and chromosomal structural rearrangements were also investigated. Lastly, candidate genes were used for pathway and gene ontology enrichment analysis., Results: Among 92 patients (mean age at stroke onset 61.0±9.3 years), GS identified likely ICAD-associated rare genomic variants in 54.3% (50/92) of patients. Forty-eight patients (52.2%, 48/92) had 59 rare SNVs/InDels reported or predicted to be deleterious in genes related to VRFs and/or other stroke subtypes. None of the 59 rare variants were identified in local subjects without ICAD (n=126). 31 SNVs/InDels were related to conventional VRFs, and 28 were discovered in genes related to other stroke subtypes. Our study also showed that rare CNVs (n=7) and structural rearrangement (a balanced translocation) were potentially related to ICAD in 8.7% (8/92) of patients. Lastly, candidate genes were significantly enriched in pathways related to lipoprotein metabolism and cellular lipid catabolic process., Conclusions: Our GS study suggests a role of rare genomic variants with various variant types contributing to the development of ICAD in Chinese patients., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Demands for expanded carrier screening (ECS) are growing and ECS is becoming an important part of obstetrics practice and reproductive planning. The aim of this study is to evaluate the feasibility of a small-size ECS panel in clinical implementation and investigate Chinese couples' attitudes towards ECS. An ECS panel containing 11 recessive conditions was offered to Chinese pregnant women below 16 gestational weeks. Sequential testing of their partners was recommended for women with a positive carrier status. The reproductive decision and pregnancy outcome were surveyed for at-risk couples. A total of 1321 women performed ECS successfully and the overall carrier rate was 19.23%. The estimated at-risk couple rate was 0.83%. Sequential testing was performed in less than half of male partners. Eight at-risk couples were identified and four of them performed prenatal diagnosis. Our study demonstrated that a small-size ECS panel could yield comparable clinical value to a larger-size panel when the carrier rate of the individual condition is equal or greater than 1%. In addition, more than half of male partners whose wives were carriers declined any types of sequential testing possibly due to a lack of awareness and knowledge of genetic disorders. Genetic education is warranted for the better implementation of ECS.

Tetrasomy 9p (ORPHA:3390) is a rare syndrome, hallmarked by growth retardation; psychomotor delay; mild to moderate intellectual disability; and a spectrum of skeletal, cardiac, renal and urogenital defects. Here we present a Chinese female with good past health who conceived her pregnancy naturally. Non-invasive prenatal testing (NIPT) showed multiple chromosomal aberrations were consistently detected in two sampling times, which included elevation in DNA from chromosome 9p. Amniocentesis was performed and sent for chromosomal microarray, which was normal. Maternal karyotype revealed that mos 47,XX,+dic(9;9)(q21.1;q21.1)(24)/46,XX(9) presents mosaic tetrasomy for the short arm of chromosome 9p and is related to the NIPT results showing elevation in DNA from chromosome 9p. The pregnancy was uneventful, and the patient was delivered at term. Maternal samples were obtained at two different time points after delivery showed the same multiple chromosomal aberrations detected during pregnancy. This is a first report on an unusual case of mosaic isodicentric tetrasomy 9p in a healthy adult with normal intellect. With widespread adoption of NIPT for screening fetal aneuploidy and genome-wide copy number changes, a rise in incidental detection of maternal rare genetic syndrome will bring challenges in our current approach to genetic counselling and prenatal diagnosis.

Objective: To report genome-wide cell-free DNA (cfDNA) screening facilitating the diagnosis of Pallister-Killian syndrome (PKS)., Methods: This is a retrospective cohort analysis of positive genome-wide cfDNA screening results showing increased signal from chromosome 12 and the detection of PKS. The genome-wide cfDNA screening results and the subsequent investigations were reviewed., Results: Three singleton pregnancies (3/29007) from 2016 to 2017 yielded positive results indicating large gains on the entire p-arm of chromosome 12. In two cases, multiple structural abnormalities were detected by prenatal ultrasound and the couples opted for termination of pregnancy. Chromosomal microarray performed on fetal skin tissues of the two abortuses detected mosaic tetrasomy 12p, consistent with PKS. In the third case, karyotype and chromosomal microarray performed on an amniotic fluid sample also showed mosaic tetrasomy 12p. In each of the three cases, genome-wide cfDNA screening revealed a large gain on chromosome 12p; subsequent prenatal or postnatal diagnostic testing confirmed the diagnosis of PKS., Conclusion: We report the ability of genome-wide cfDNA screening to provide early suspicion and facilitate the subsequent genetic diagnosis of PKS. As genome-wide cfDNA screening becomes increasingly available, incidental diagnosis of partial aneuploidies is expected to increase., (© 2020 John Wiley & Sons, Ltd.)

Autosomal dominant types of nonsyndromic hearing loss (ADNSHL) are typically postlingual in onset and progressive. High genetic heterogeneity, late onset age, and possible confounding due to nongenetic factors hinder the timely molecular diagnoses for most patients. In this study, exome sequencing was applied to investigate a large Chinese family segregating ADNSHL in which we initially failed to find strong evidence of linkage to any locus by whole-genome linkage analysis. Two affected family members were selected for sequencing. We identified two novel mutations disrupting known ADNSHL genes and shared by the sequenced samples: c.328C>A in COCH (DFNA9) resulting in a p.Q110K substitution and a deletion c. 2814&#95;2815delAA in MYO6 (DFNA22) causing a frameshift alteration p.R939Tfs*2. The pathogenicity of novel coding variants in ADNSHL genes was carefully evaluated by analysis of co-segregation with phenotype in the pedigree and in light of established genotype-phenotype correlations. The frameshift deletion in MYO6 was confirmed as the causative variant for this pedigree, whereas the missense mutation in COCH had no clinical significance. The results allowed us to retrospectively identify the phenocopy in one patient that contributed to the negative finding in the linkage scan. Our clinical data also supported the emerging genotype-phenotype correlation for DFNA22., (© 2014 John Wiley & Sons Ltd/University College London.)

Aims: To examine the additive effect of the z-4 microsatellite polymorphism of aldose reductase gene (ALR2) and glycaemic control on risk of cataract in a prospective cohort of Chinese type 2 diabetic patients., Methods: The (CA)n microsatellite polymorphism of ALR2 was determined using PCR followed by capillary gel electrophoresis. Cataract was defined by presence of lens opacity on direct ophthalmoscopy or history of cataract surgery. A non-linear curve approach was used to identify the threshold of glycated hemoglobin (HbA1c) at which the odds ratio (OR) for cataract started to increase. The association of z-4 allele with cataract, above and below this threshold, was assessed using multiple logistic regression analysis., Results: Of the 5823 patients analyzed, 28.1% had cataracts. After adjusting for conventional risk factors and using non-z-4 carriers with HbA1c<8.0% as referent group (n = 3173), the OR (95% confidence intervals) for cataract was highest in z-4 carriers with HbA1c ≥ 8.0% [1.43 (1.05-1.96), n = 244], compared to non-z-4 carriers with HbA1c ≥ 8.0 [1.27 (1.10-1.47), n = 1836] and z-4 carriers with HbA1c<8.0%[1.01 (0.77-1.29), n = 420, P(trend) < 0.001]. This additive association remained significant after additional adjustments for drug use (P(trend) = 0.002) and renal function (P(trend) = 0.01)., Conclusions: In type 2 diabetic patients with suboptimal glycaemic control, the z-4 allele of ALR2 (CA)n polymorphism was independently associated with increased susceptibility to cataracts., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Introduction and Hypothesis: The purpose of this study was to investigate the reliability and validity of the Chinese version of Pelvic Floor Distress Inventory (PFDI) and Pelvic Floor Impact Questionnaire (PFIQ)., Methods: Women who presented for pelvic floor disorders completed the Chinese version of PFDI and PFIQ, SF-36, a 3-day urinary and fecal diary. POP-Q assessment, urodynamic study, anal manometry, and ultrasound were performed where appropriate., Results: Five hundred and ninety-seven women completed the study. The Cronbach's alpha and test-retest reliability of PFDI and PFIQ was 0.92 and 0.98, and 0.77 and 0.79, respectively. Convergent validity was demonstrated with negative correlation of PFDI and PFIQ with SF-36; positive correlation of staging of prolapse, urinary or fecal incontinent episodes with the respective subscales of PFDI and PFIQ., Conclusions: The Chinese version of PFDI and PFIQ are reliable and valid condition-specific health-related quality of life questionnaires for women with pelvic floor disorders.

Objective: To determine the genetic cause of sex reversal in a Chinese family., Methods: Two sisters aged 21 and 20 years old were referred for primary amenorrhoea and poor secondary sexual development. They were subjected to clinical, endocrinologic and ultrasonographic investigation, and molecular analysis including cytogenetics, array CGH, SRY and SF-1 mutation screening., Results: A novel 15bp micro-duplication in the SF-1 gene in patients affected by 46,XY sex-reversal phenotype without dysgenesis., Conclusion: The novel 15bp duplication of SF-1 gene affecting 46,XY females with diverse phenotypic spectrum. This provides new information for genetic counselling of disorders of sex development.

Purpose: The purpose of this study was to investigate the BEST1 gene mutations in Chinese patients with Best vitelliform macular dystrophy (BVMD)., Methods: Twenty-six subjects from 7 Chinese families with BVMD and 100 unrelated healthy Chinese subjects without a family history of BVMD were screened for mutations in the BEST1 gene by direct sequencing. The subjects underwent complete ophthalmologic examination and BEST1 gene screening., Results: Six novel missense mutations (Thr2Asn, Leu75Phe, Ser144Asn, Arg255Trp, Pro297Thr, and Asp301Gly) and 1 previously reported mutation (Arg218Cys) were identified. Each family was found to have a unique BEST1 mutation that segregated with the disease. Two of the six novel mutations are located within the four previously reported common mutation clusters within the BEST1 gene. One family with patients having homozygous Leu75Phe mutations did not have the more severe BVMD phenotype. None of the patients with mutations was identified among the 100 healthy control subjects., Conclusion: A large number of unique novel missense mutations was found in Chinese patients with BVMD, suggesting considerable interethnic differences between the mutation sites in the BEST1 gene in different populations. The few truncating BEST1 mutations and the lack of a more severe phenotype in homozygous patients suggest that the missense BEST1 mutation may produce a dominant negative effect on wild-type BEST1 gene.

Objective: To assess Chinese women's preference for the choice of a prenatal diagnosis test, karyotyping or rapid aneuploidy, and its relationship to maternal psychological state., Study Design: Three hundred consenting women completed a self administered structured questionnaire which documented their psychological state and their preferred choice of diagnostic test for chromosomal abnormality using a discrete choice experiment design. Diagnostic tests were categorised according to three attributes: completeness of chromosomal information, procedure-to-result time interval and cost., Results: Participants indicated a preference towards the karyotype test irrespective of cost and procedure-to-result time interval. The value of obtaining the extra information provided by karyotyping above that of rapid aneuploidy was pound267.82 (95% CI 226.71-323.31). Women would only accept the rapid aneuploidy test if results where available 18 days sooner than if they were undergoing a karyotyping test. Among women who traded between diagnostic tests, the value of extra chromosomal information was reduced to pound153.83 (95% CI 125.81-192.19). Women with high trait anxiety scores (>40) did not preferentially select one test., Conclusion: Chinese women showed a strong preference towards performing a full karyotype test and having a full chromosomal assessment performed for their pregnancy., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

Purpose: We tested the hypothesis that genetic variants in vasoactive and angiogenic factors regulating the retina vasculature contribute to the development of diabetic retinopathy (DR)., Methods: A case-control study was performed to study the genetic association between DR and polymorphic variants of EDN1 (Lys198Asn), LTA (IVS1-80C>A, IVS1-206G>C, IVS1-252A>G), eNOS (Glu298Asp), and ITGA2 (BgI II) in a Chinese population with type 2 diabetes mellitus. A well defined population with type 2 diabetes, consisting of 127 controls and 216 DR patients, was recruited., Results: A higher frequency of the Asn/Asn genotype of EDN1 was found in individuals with at least 10 years of diabetes and no retinopathy (controls) compared with DR patients with any duration of diabetes (DR: 2.3%; control: 11.0%; p=0.0002). The Asn allele was also more frequent in controls than DR patients (DR: 16.4%; control: 29.5%; p=0.007). Multiple logistic regression analysis showed that the Asn/Asn genotype was the factor most significantly associated with reduced risk of DR (odds ratio=0.19; 95% CI: 0.07-0.53; p=0.002) and with late onset of diabetes (Asn/Asn: 59 years; Lys/Lys + Lys/Asn: 53 years; p=0.02). Moreover, the Lys/Lys genotype was more common among patients with nonproliferative (75.7%) than proliferative DR (56.9%; p=0.008). The distributions of Lys198Asn alleles in hypertension did not differ from normotensive subjects. No associations between DR and polymorphisms of LTA, eNOS, or ITGA2 were detected, and there were no detectable gene-gene or gene-environmental interactions among the polymorphisms., Conclusions: The Asn/Asn genotype of EDN1 was associated with a reduced risk of DR and with delayed onset of type 2 diabetes.

We investigated sequence alternation, promoter methylation, and loss of heterozygosity (LOH) of the RB1 gene as possible mechanisms of its inactivation in retinoblastoma. In 42 Chinese patients with sporadic retinoblastoma, the promoter and entire coding region of RB1 were examined for sequence changes. Status of methylation of the CpG-rich island at the 5'end was determined by methylation specific PCR assay. We detected 15 RB1 mutations in 38% (16/42) of the retinoblastoma patients, among them 19% (8/42) were germ-line mutations. A total of nine novel mutations were identified: E54X, S114X, I126S, g73779insG, D718N, IVS2+1G>C, IVS14+1G>C, IVS21+1G>C, and a complex alteration g78177G>T/g78176insTT leading to 543X. Most of them are likely to affect the RB1large pocket domain through the production of truncated gene products. None of the DNA samples showed methylation at the RB1promoter. In 15 cases where both normal and cancerous retinoblastoma tissue specimens were available, allelic loss according to microsatellite markers within or distal to the RB1 locus was analyzed and immunohistological staining for RB1 expression performed. Among them, frequency of LOH at 13q14 was found to be high at 60% (9/15) with no segregation with unilateral tumors. All these nine tumors did not express RB1 protein, showing an association of LOH at the RB1 locus with its loss of expression in retinoblastoma. Our results indicate that the RB1 gene in sporadic retinoblastoma is commonly inactivated because of loss-of-function mutations and loss of heterozygosity but not by the epigenetic phenomenon of promoter hypermethylation., (Copyright 2002 Wiley-Liss, Inc.)