A Retrospective Review of Copy Number Variants and Ultrasound-Detected Soft Markers

Abstract

Objective: To examine the association of copy number variants (CNV) among fetuses with ultrasound-detected soft markers (USM).  Methods: This IRB-approved retrospective cohort study of fetuses with prenatal or children with postnatal chromosomal microarray analysis (CMA) sought to examine an association between clinically relevant CNV (classified as pathogenic CNV or variants of uncertain significance (VUS)) and USM in women who delivered at Geisinger between January 2010 and July 2018. The following USM were evaluated: choroid plexus cyst, thickened nuchal fold, absent or hypoplastic nasal bone, echogenic intracardiac focus, echogenic bowel, short long bones, and urinary tract dilation. Fetuses or children with known aneuploidy or a single gene disorder were excluded. Odds ratios (OR) of the association between CNV and USM were reported along with associated 95% confidence intervals (CI) and p-values. P values <0.05 were considered significant.  Results: Of the 348 fetuses/children, 89 (25.6%) had a clinically relevant CNV. Similar percentages of demographic, delivery and neonate characteristics were noted for those with a clinically relevant CNV and those with a normal microarray analysis. No statistically significant differences were noted among those fetuses/children with a clinically relevant CNV and structural anomaly (p = 0.52; OR 1.18, 95% CI 0.72-1.92), presence of one USM (p = 0.72; OR 1.52, 95% CI 0.79-2.92), or presence of more than one USM (p = 0.79; OR 1.56, 95% CI 0.28-8.72).  Conclusion: Our data supports a lack of association between a clinically relevant copy number variant and an ultrasound-detected soft marker. A small statistically insignificant increase in odds of a clinically relevant CNV was noted for those fetuses/children with one or more USM.