OBJECTIVE: The purpose of this research was to attempt a preliminary study of noninvasive prenatal diagnosis of Down syndrome in Southwest Chinese gravidas by using the plasma placental RNA allelic ratio. METHODS: The genotypes of the single-nucleotide polymorphisms (SNPs) located in the transcribed regions of the gene PLAC4 were detected in population samples collected in Southwest China by using polymerase chain reaction-restriction fragment length polymorphism, and SNPs with a higher heterozygosity were selected. Mass spectrometer analysis was adopted, and cases with the heterozygous SNPs on PLAC4 mRNA in maternal plasma were selected from 29 pregnancies with a euploid fetus and from 21 pregnancies with a trisomy-21 fetus, and then their RNA-SNP allelic ratios were further determined for noninvasive prenatal diagnosis of Down syndrome. RESULTS: Of all 50 singleton pregnancies, 37 gravidas were found with at least one heterozygous SNP on PLAC4 mRNA in maternal plasma. Among them, 13 pregnancies with a trisomy-21 fetus were detected by the analysis of the RNA-SNP allelic ratio. CONCLUSION: The plasma placental RNA allelic ratio can be used for noninvasive prenatal diagnosis of Down syndrome, if SNPs on PLAC4 mRNA in maternal plasma are heterozygous.
OBJECTIVE: The purpose of this research was to attempt a preliminary study of noninvasive prenatal diagnosis of Down syndrome in Southwest Chinese gravidas by using the plasma placental RNA allelic ratio. METHODS: The genotypes of the single-nucleotide polymorphisms (SNPs) located in the transcribed regions of the gene PLAC4 were detected in population samples collected in Southwest China by using polymerase chain reaction-restriction fragment length polymorphism, and SNPs with a higher heterozygosity were selected. Mass spectrometer analysis was adopted, and cases with the heterozygous SNPs on PLAC4 mRNA in maternal plasma were selected from 29 pregnancies with a euploid fetus and from 21 pregnancies with a trisomy-21 fetus, and then their RNA-SNP allelic ratios were further determined for noninvasive prenatal diagnosis of Down syndrome. RESULTS: Of all 50 singleton pregnancies, 37 gravidas were found with at least one heterozygous SNP on PLAC4 mRNA in maternal plasma. Among them, 13 pregnancies with a trisomy-21 fetus were detected by the analysis of the RNA-SNP allelic ratio. CONCLUSION: The plasma placental RNA allelic ratio can be used for noninvasive prenatal diagnosis of Down syndrome, if SNPs on PLAC4 mRNA in maternal plasma are heterozygous.
Authors: Y M Dennis Lo; Nancy B Y Tsui; Rossa W K Chiu; Tze K Lau; Tse N Leung; Macy M S Heung; Ageliki Gerovassili; Yongjie Jin; Kypros H Nicolaides; Charles R Cantor; Chunming Ding Journal: Nat Med Date: 2007-01-07 Impact factor: 53.440
Authors: Nancy B Y Tsui; Ranjit Akolekar; Rossa W K Chiu; Katherine C K Chow; Tak Y Leung; Tze K Lau; Kypros H Nicolaides; Y M Dennis Lo Journal: Clin Chem Date: 2009-11-05 Impact factor: 8.327
Authors: H Christina Fan; Yair J Blumenfeld; Usha Chitkara; Louanne Hudgins; Stephen R Quake Journal: Proc Natl Acad Sci U S A Date: 2008-10-06 Impact factor: 11.205