Popis: |
Since the discovery of cell-free fetal DNA in peripheral blood of pregnant women, cell-free nucleic acids in maternal plasma are explored in relation to non-invasive prenatal diagnosis of various fetal conditions and pregnancy complications. Non-invasive prenatal diagnosis of monogenic diseases represented by TSC1-linked tuberous sclerosis could be achieved by detection of paternally-inherited mutant allele in the pool of maternal alleles in plasma. Reliability of detection of mutant allele could be improved by simultaneous mutation haplotype analysis or detection of universal fetal marker. None of the 3 methods (allele- specific real-time PCR, SNaPshot minisequencing and quantitative fluorescent PCR) evaluated using artificial mixtures and maternal plasma samples reliably and accurately detected low-frequency allele distinguished by point mutation, SNP or microsatellite in TSC1 gene or in its close proximity. We developed a strategy for prediction of proportion of informative couples for panel of SNPs of interest that can be applied to any monogenic disease. Exploiting differential methylation of promoters of genes RASSF1A, HLCS and OLIG2 in maternal and fetal genome, we failed to establish functional fetal marker. MicroRNAs of placental origin released into plasma could serve as biomarkers of... |