MTHFR C677T and A1298C Gene Polymorphisms and Ischemic Heart Disease (IHD) in a Sri Lankan Population – A Preliminary Study
MTHFR A1298C and C677T SNPs are now recognized as important genetic mutations which would give rise to hyperhomocysteinemia. In this study we analyzed the prevalence of these two SNPs in 79 IHD patients awaiting coronary artery bypass grafting and 79 healthy subjects. MHFR polymorphisms were analyzed using polymerase chain reaction followed by restriction fragment analysis.
Prevalence rates for MTHFR C677T polymorphism were 72.8%, 24.7% and 2.5% for CC, CT and TT genotypes respectively for the whole study population with 677CC genotype being the predominant genotype among both the IHD patients and the controls. The 677TT genotype was detected only among the IHD patients. There was no significant difference in MTHFR 677 genotype variations between IHD patients and the control group. Prevalence rates for the MTHFR A1298C polymorphism were 50%, 37.3% and 12.7% for the AA, AC and CC genotypes respectively for the whole study population with 1298AA genotype being the predominant genotype among controls and 1298AC the predominant genotype among IHD patients. There was a significant difference (p < 0.01) between IHD patients and controls when the MTHFR 1298 genotype variations were compared.
Allele frequencies for the mutant T allele for C677T mutation at 0.149 is the highest reported from Sri Lanka. The frequency of the C for the A1298C mutation was 0.313.
Results of this study indicate that MTHFR A1298C SNP is more prevalent in Sri Lankans when compared to C677T SNP and that the mutant forms of the MTHFR A1298C SNP are associated with ischemic heart disease.
Keywords: Methylene tetrahydrofolate reductase, Single Nucleotide polymorphisms, Ischemic heart disease.
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