Association of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms with coronary artery disease (CAD) in a North Indian population

There is significant variation in reported associations of the MTHFR C677T (rs1801133) and A1298C (rs1801131) polymorphisms and coronary artery disease (CAD) in different global populations. This study aims to identify any individual or combined associations between the 1298 and 677 loci of MTHFR and CAD in a North Indian population. A total of 159 patients and 166 controls were genotyped using validated TaqMan assays. Odds ratio analysis identified associations at crude level and multiple logistic regression controlled for confounding variables. Linkage disequilibrium between the loci was assessed along with haplotype association analysis. At the C677T locus, homozygosity of the T allele identified a significantly protective association (OR = 0.38, CI: 0.24–0.60). For the A1298C locus the AC genotype had a protective effect in codominant model (OR = 0.53, CI: 0.32–0.85) and CC genotype showed a susceptible association in recessive model when controlled for age, sex and lipids (OR = 2.70, CI: 1.27–5.77). This study identified that, independently, both heterozygous genotypes show a protective association with CAD. In addition the CC genotype of A1298C in recessive model was a susceptible genotype. The combined associations of MTHFR are protective (primarily due to the effects of C677T locus) suggesting an interaction between the loci and their associations with CAD within this sample.