Hypermethylated RASSF1A in Maternal Plasma: A Universal Fetal DNA Marker that Improves the Reliability of Noninvasive Prenatal Diagnosis

摘要: Background: We recently demonstrated that the promoter of RASSF1A gene is hypermethylated in placenta and hypomethylated maternal blood cells. This methylation pattern allows use methylation-sensitive restriction enzyme digestion for detecting placental-derived sequences plasma. Methods: performed real-time PCR after to detect plasma 28 1st-trimester 43 3rd-trimester pregnant women. used perform prenatal fetal rhesus D (RhD) group typing 54 early-gestation RhD-negative women, with as positive control DNA detection. Results: Hypermethylated were detectable all 71 The genotype was identical each case, thus confirming its origin. Nineteen women undergoing RhD genotyping showed undetectable RHD their samples. control, , not 4 19 Subsequent chorionic villus sample analysis revealed 2 these negative signals fact carrying RhD-positive fetuses. Conclusions: a universal marker readily plasma. When applied genotyping, this detection false-negative results caused by low concentrations new can also be many other diagnostic monitoring scenarios.