Relationship between genetic polymorphisms of angiotensin-converting enzyme and methylenetetrahydrofolate reductase as risk factors for type 2 diabetes in Tunisian patients

Background/aimsThe role of methylenetetrahydrofolate reductase (MTHFR) and angiotensin-converting enzyme (ACE) gene polymorphisms as being risk factors for diabetes is still controversial. The aim was to investigate the distribution of ACE and MTHFR genotypes as well as to evaluate the role of plasmatic total homocysteine levels (tHcy) and ACE activity in Tunisian patients with type 2 diabetes mellitus (T2DM).Design and methods115 T2DM patients compared to 116 healthy volunteers.ResultsThe ACE I/D polymorphism was significantly associated with diabetes (p < 0.0001). The DD genotype and D allele were more frequent in patients compared to control group [DD: OR = 4.93; p < 0.0001; 95 % CI: 2.71–8.97; D: OR = 3.08, 95% CI: 2.09–4.51 p < 0.0001]. MTHFR allele and genotype frequencies did not differ between patients and controls. The susceptibility to diabetes in individuals with genotypes DD +vTT was 13.39 and in the individuals with DD + CT was 6.57 times that of the controls. However, individuals with genotypes ID + CC or II + CT have a protective effect against diabetes. The DD and TT genotypes were associated with significantly higher ACE activity and tHcy levels in diabetics.ConclusionOur data suggest that ACE ID polymorphism may act synergistically with MTHFR C677T polymorphism to assess diabetes risk.