Impact of mosaicism ratio on positive predictive value of cfDNA screening.

ABSTRACT:

Objective

To examine the relationship between the fraction of cell-free DNA (cfDNA) affected by aneuploidy compared to the overall fetal fraction of a prenatal screening specimen and its effect on positive predictive value (PPV).

Method

CfDNA specimens positive for trisomy 13, 18, and 21 with diagnostic outcomes were analysed over a 22-month period in one clinical laboratory. For each positive specimen, a "mosaicism ratio" (MR) was calculated by dividing the fraction of cfDNA affected by aneuploidy by the overall fetal fraction of the specimen. PPVs were calculated and analyzed based on various MR ranges.

Results

Trisomy 13 was the aneuploidy most commonly seen in mosaic form, followed by trisomy 18 and trisomy 21. Significant differences in positive predictive values

SUBMITTER: Rafalko JM 

PROVIDER: S-EPMC7894494 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature