Association of MTHFR and PPARγ2 gene polymorphisms in relation to type 2 diabetes mellitus cases among north Indian population

Background: Type 2 diabetes mellitus is a multifactorial and polygenic disease, which is considered as a major life threatening problem all over the world. There has been a worldwide effort in the identification of susceptibility genes for type 2 diabetes mellitus and its complications. At present, adequate data is not available dealing with MTHFR (rs1801133) and PPAR gamma 2 (rs1801282) gene polymorphisms and its association with type 2 diabetes mellitus cases among north Indian populations. Thus, we conceived the need for further studies to investigate MTHFR and PPAR gamma 2 gene polymorphisms and their susceptibility to type 2 diabetes mellitus in north Indian population. Materials and methods: In this study, a total 175 subjects including 87 type 2 diabetes mellitus cases and 88 controls were enrolled. MTHFR and PPAR gamma 2 gene polymorphisms in the cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Results: The MTHFR gene CC, CT, TT genotype frequencies obtained were 40%, 43%, and 17% in type 2 diabetes mellitus cases and 56%, 29%, and 15% in healthy controls respectively. The OR for CC was 0.54 (95%CI 0.29-0.98, P = 0.041, chi(2)=4.18, power = 0.98), for CT 1.76 (95%CI 0.94-3.30, P = 0.07, chi(2)=3.2, power = 0.96), and for TT 1.2 (95%CI 0.53-2.70, P = 0.66, chi(2)=0.198, power = 0.76). The PPAR gamma 2 gene GG CG, CC genotype frequencies obtained were 28%, 41%, and 31% in cases and 40%, 39%, and 21% in healthy controls respectively. OR for GG was 0.58 (95%CI 0.30-1.09, P = 0.08, chi(2) = 2.9, power = 0.96), for CG 1.12 (95%CI 0.61-2.05, P = 0.71, chi(2)=0.137, power = 0.778), and for CC 1.63 (95%CI 0.82-3.23, P = 0.156, chi(2) = 2.01, power = 0.92). Conclusion: It might be recommended that MTHFR CC genotype seems to be a good marker for the early identification of population at risk of type 2 diabetes mellitus. While we have detected significant difference in allelic frequencies of PPAR gamma 2 C (Proline) and G (Alanine), but at genotypic level significant difference was not detected in this case-control study. Further study with larger groups may be required to validate the study. (C) 2012 Elsevier B.V. All rights reserved.