Related Experiment Video
Updated: Feb 19, 2026
Pre-Implantation Genetic Testing for Aneuploidy on a Semiconductor Based Next-Generation Sequencing Platform
Published on: August 17, 2022
Comparison of first-tier cell-free DNA screening for common aneuploidies with conventional publically funded
Sylvie Langlois1, JoAnn Johnson2, François Audibert3
1Dept. of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.
Objective:
This study evaluates the impact of offering cell-free DNA (cfDNA) screening as a first-tier test for trisomies 21 and 18.
Methods:
This is a prospective study of pregnant women undergoing conventional prenatal screening who were offered cfDNA screening in the first trimester with clinical outcomes obtained on all pregnancies.
Results:
A total of 1198 pregnant women were recruited. The detection rate of trisomy 21 with standard screening was 83% with a false positive rate (FPR) of 5.5% compared with 100% detection and 0% FPR for cfDNA screening. The FPR of cfDNA screening for trisomies 18 and 13 was 0.09% for each. Two percent of women underwent an invasive diagnostic procedure based on screening or ultrasound findings; without the cfDNA screening, it could have been as high as 6.8%. Amongst the 640 women with negative cfDNA results and a nuchal translucency (NT) ultrasound, only 3 had an NT greater or equal to 3.5 mm: one had a normal outcome and two lost their pregnancy before 20 weeks.
Conclusions:
cfDNA screening has the potential to be a highly effective first-tier screening approach leading to a significant reduction of invasive diagnostic procedures. For women with a negative cfDNA screening result, NT measurement has limited clinical utility.
