Clinical Performance of Non-invasive Prenatal Testing for Sex Chromosomal Aneuploidies in Northeast China

Background: Along with the discovery of cell-free DNA (cfDNA) and the invention of next-generation sequencing (NGS), non-invasive prenatal testing (NIPT) had appeared and been applied for detecting common aneuploidies such as trisomy 21, 18, and 13, with low false-negative and false-positive rates. Recently, it had also been used for sex chromosome aneuploidies (SCAs). To assess the clinical utility of NIPT for SCAs in Northeast China, we collected NIPT data from BGI 500 sequencing platform in the Center for Reproductive Medicine, Center for Prenatal Diagnosis of the First Hospital of Jilin University, and calculate the positive predictive value (PPV) and false positive rate (FPR). Results: A cohort of 14936 samples were analyzed by NIPT, and revealed 70 cases with SCAs high-risk, among them, 40 women agreed to undergo amniocentesis, but as many as 30 ones refused further diagnose. Based on verified fetal karyotype, 30.0% (12/40) were confirmed to be a true positive. Unluckily, the PPV for monosomy X performed 0%. Besides, positive 47,XXX were 46.67% (7/15), 40.00% (2/5) were positive for 47, XYY, and 42.86% (3/7) were positive for 47, XXY. Conclusions: In conclusion, our present results confirmed that NIPT sequenced by BGI 500 demonstrated lowest PPVs for 45,X, but the more accurate prediction for other SCAs, it is still a potential method for SCAs screening. Henceforth, we should focus on how to improve the test utility and provide better services for pregnant women in need.