Performance et indication du dépistage des trisomies 21, 18 et 13 en France par l’analyse de l’ADN fœtal dans le sang maternel

Abstract

To evaluate de performances of noninvasive prenatal testing using cell free circulating fetal DNA (cffDNA) for the detection of fetal trisomy 21, 18and 13in a French population. cffDNA analysis was performed by massive parallel sequencing during a multicenter, non interventional, prospective study and the results were compared with a standard fetal karyotype. Results were available for 886patients who have been classified as high- or moderate-risk depending on the presence of fetal abnormalities on ultrasound examination. For the high-risk group (n=376), the sensitivity and specificity of the test were 100% and 99.9% for trisomy 21, 88% and 99.9% for trisomy 18and 100% and 99.9% for trisomy 13. The rate of other pathogenic chromosomal abnormalities with a negative NIPT was 7.9%. In the low-risk group (n=510), the sensitivity was 100% and the specificity 99.8% for trisomy 21, and only 0.4% of pathogenic chromosomal abnormalities were revealed by fetal karyotyping but not detected by cffDNA analysis. Noninvasive prenatal testing using cffDNA for high risk patients without fetal anomalies at ultrasound could be recommended in France after counseling on the possible risk of undiagnosed anomalies.