Analysis of multiple loci can increase reliability of detection of fetal Y-chromosome DNA in maternal plasma

Abstract

Objective: Aiming to develop more reliable methods for determination of fetal gender from maternal plasma we compared three different systems of polymerase chain reaction (PCR) detection of Y-chromosome DNA.

Methods: Cell-free DNA was isolated from 96 samples of maternal plasma and (1) amplified using AmpFLSTR-Identifiler (15 autosomal STR loci and amelogenin) or AmpFLSTR-Yfiler (16 Y-chromosome STR loci) kits and subsequently analyzed on ABI-PRISM 310 Genetic Analyzer, or (2) analyzed using Quantifiler-Y DNA-Quantification kit. Gender of fetuses was confirmed by cytogenetic analysis or phenotypically at birth.

Results and conclusions: AmpFLSTR-Identifiler and Quantifiler-Y Human-Quantification kits were rather reliable in determining fetal gender (92.5 and 98.1%, respectively), but false negatives were still present in both systems. AmpFLSTR-Yfiler was found to be fully reliable as it amplified Y-chromosome in all cases of male fetuses, and was thus 100% correct in determining fetal gender. In addition, it enabled comparison of polymorphic Y-chromosome loci between father and a child, thus further supporting specificity of obtained results.