Variable R.Msp1 fragmentation in genomic DNA due to DNA hypomethylation in CRF patients with MTHFR C677Tgene polymorphism: From genetics to epigenetics

Abstract

The role of inflammation, hyperhomocysteinemia, germ-line genetic markers and epimutations haven't been understood completely in chronic renal failure (CRF). DNA methylation is a postreplicative modification mechanism that is strongly involved in the physiological control of epimutations and gene expression. In the current study it was aimed to find out the possible role of epigenetic alterations in renal failure due to functional MTHFR deficiency in CRF patients requiring long-term haemodialysis. Current cohort includes 228 CRF patients and 212 healthy individuals from same ethnicity. The MTHFR C677T SNP analysis was genotyped by real-time PCR analysis. Genomic DNA fragmentation sizes were correlated for wild, heterozygous and homozygous mutated CRF patients after methyl marker cognate enzyme of R.Msp1 digestion. The digested DNA fragmentation profiles were also compared by Scion Image histogram plot analysis. Increased T allele frequency was detected in CRF patients, the MTHFR 677TT genotype was found 6.1% and the T allele frequency 2.53-fold increased in CRF when compared with healthy individuals. Distinct global DNA methyl patterns that showed variable R.Msp1 fragmentations were also detected in current MTHFR gene mutated CRF patients. The current results indicate that individuals with germ-line MTHFR C677T mutations have a risk for CRF pathogenesis due to the reduced enzyme activity and global DNA hypomethylation that alters the allelic expression of distinct systemic genes. Results needs to be confirmed by a larger scale of sample size.