MTHFR 677C>T (rs1801133) variant is associated with homocysteinemia but not with clinical severity in patients with peripheral arterial occlusive disease

Objective: The aim was to evaluate the association between the MTHFR 677C>T (rs1801133) variant with susceptibility and severity of peripheral arterial occlusive disease (PAOD) and levels of homocysteine (Hcy). Subject and Methods: A case-control study enrolled 157 patients with PAOD and unrelated 113 controls. The severity and anatomoradiological categories of the PAOD were assessed by Fontaine classification and Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC), respectively. The MTHFR 677C>T was genotyped using real-time polymerase chain reaction and Hcy serum levels were determined using chemiluminescence microparticles assay. Results: : The PAOD patients showed higher Hcy than controls but the values did not differ according to Fontaine and TASC categories. The MTHFR 677C>T variant was not associated with PAOD, the clinical stage, and the anatomoradiological categories. However, patients carrying the TT genotype (recessive model) or CT+ TT genotypes (dominant model) presented higher levels of Hcy than those carrying other genotypes. In conclusion, the T allele of MTHFR 677C>T variant was associated with hyperhomocysteinemia in PAOD patients, but not in controls. Conclusion: Our data suggested a possible interaction between MTHFR 677C>T variant and the presence of other genetic, epigenetic or environment factors associated with PAOD on modulation of the Hcy metabolism.