P16.01: The value of prenatal chromosomal microarray analysis in fetuses with structural ultrasound abnormalities and a normal karyotype in China

Abstract

The aim of this study was to evaluate the contribution of chromosomal microarray analysis (CMA) in the prenatal diagnosis of fetuses with structural anomalies but normal chromosomal karyotype. Fetuses with structural anomalies underwent chromosome conventional G-banding karyotyping. Fetuses with normal karyotype were performed on CMA including the array-based comparative genomic hybridisation (aCGH) and array-single-nucleotide polymorphism (SNP). Out of the 402 pregnancies with structural ultrasound abnormalities, karyotyping revealed a chromosomal abnormality in 33 (8.2%). Among fetuses with structural ultrasound abnormalities and normal karyotype(n=369) that underwent CMA, the detection rate of copy number variants (CNV) was 22.2% (82/369), including pathogenic CNV in 11.4% (42/369) and variants of uncertain clinical significance (VOUS) in 10.8% (40/369). In the groups of cardiac, central nervous, musculoskeletal, facial and urogenital malformations, the rate of the pathogenic CNV were 16.6% (38/229), 21.9% (14/64), 15.5% (15/97), 13.5% (7/52) and 18.8% (6/32) respectively. Ultrasound anomaly restricted to one anatomical system (n=238) had a 10.5% (n=25) chance of carrying a pathogenic CNV, while this chance increased to 13.0% (n=17) for multiple ultrasound anomalies (n=131). Supporting information can be found in the online version of this abstract Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.