Adherence of cell-free DNA noninvasive prenatal screens to ACMG recommendations

Noninvasive prenatal screening (NIPS) for fetal aneuploidy via cell-free DNA has been commercially available in the United States since 2011. In 2016, the American College of Medical Genetics and Genomics (ACMG) issued a position statement with specific recommendations for testing laboratories. We sought to evaluate adherence to these recommendations.

We focused on commercial laboratories performing NIPS testing in the United States as of 1 January 2018. Sample laboratory reports and other materials were scored for compliance with ACMG recommendations. Variables scored for common and sex chromosome aneuploidy detection included detection rate, specificity, positive and negative predictive value, and fetal fraction. Labs that performed analysis of copy-number variants and results for aneuploidies other than those commonly reported were identified. Available patient education materials were similarly evaluated.

Nine of 10 companies reported fetal fraction in their reports, and 8 of 10 did not offer screening for autosomal aneuploidies beyond trisomy 13, 18, and 21. There was inconsistency in the application and reporting of other measures recommended by ACMG.

Laboratories varied in the degree to which they met ACMG position statement recommendations. No company adhered to all laboratory guidance.