Clinical experience of noninvasive prenatal testing for rare chromosome abnormalities in singleton pregnancies.

Hu T, Wang J, Zhu Q, et al. Front Genet. 2022;13:955694. Published 2022 Sep 26. doi:10.3389/fgene.2022.955694. Open Access: Learn more

Tags: Clinical Experience / Clinical Utility, 2022, China, RAAs, CNVs

  • “The screen-positivity rate of NIPT for RCAs [rare chromosomal abnormalities] was 0.5% (842/158,824). Of the 528 gravidas who underwent amniocentesis, 29.2% (154/528) were confirmed to have positive prenatal SNP (single nucleotide polymorphism) array results. PPVs for rare autosomal trisomies (RATs) and segmental imbalances were 6.1% (7/115) and 21.1% (87/413), respectively. Regions of homozygosity/uniparental disomy (ROH/UPD) were identified in 9.5% (50/528) of gravidas. The PPV for clinically significant findings was 8.0% (42/528), including 7 cases with mosaic RATs, 30 with pathogenic/likely pathogenic copy number variants, and 5 with imprinting disorders.”