Context: Previous studies reported an association of 677 C-->T and 1298 A-->C methylenetetrahydrofolate reductase (MTHFR) variants with coronary artery disease (CAD). No previous studies concerning the prevalence of these 2 MTHFR variants or their possible association with CAD in Arabs are currently available in the literature.
Objective: To determine the prevalence of MTHFR variants and their potential relevance to CAD among Arabs.
Design: We used polymerase chain reaction and restriction enzyme digestion to determine the prevalence of these 2 MTHFR polymorphisms in 625 healthy blood donors (BDs) and 545 angiographically confirmed CAD patients of Arab origin.
Results: For the 677 C-->T variant within the CAD group, 64.2% were homozygous wild-type C/C, 32.1% were heterozygous C/T, and 3.7% were homozygous T/T genotype. Within the BD group tested for the 677 C-->T variant, 72.2% were homozygous wild-type C/C, 25.8% were heterozygous C/T, and 2% were homozygous T/T genotype. Within the CAD group tested for the 1298 A-->C variant (n = 540), 45.7% were homozygous wild-type A/A, 46.9% were heterozygous A/C, and 7.4% were homozygous C/C genotype. Within the BD group tested for the 1298 A-->C variant (n = 625), 39.4% were homozygous wild-type A/A, 51.5% were heterozygous A/C, and 9.1% were homozygous C/C genotype. The distribution and allele frequency of these 2 MTHFR variants followed the Hardy-Weinberg equilibrium and were similar in the CAD and BD study groups. The prevalence of the 677 C-->T and 1298 A-->C compound heterozygosity was 9.6% for the BD group and 12.3% for the CAD group.
Conclusion: The 2 MTHFR variants tested in this study, individually or compound, are not associated with CAD. Therefore, neither of these 2 variants can be considered an independent risk factor or a predictor for CAD in this population.