Association between PRO12ALA polymorphism at the PPARγ2 gene and insulin sensitivity in South Indian population with type 2 diabetes mellitus

Peroxisome Proliferator Activated Receptors (PPAR) are members of the nuclear receptor superfamily of ligand activated transcription factor consisting of 3 subtypes PPARα , PPARβ and PPARγ. PPARγ plays an important role in adipocyte differentiation and it regulates lipid metabolism as well as insulin sensitivity. Of the 3 isoforms of PPARγ, PPARγ2 are expressed in adipose tissue. Genomic DNA was obtained from 75 Type II Diabetes Mellitus cases and 75 controls. Biochemical parameters included fasting plasma glucose and fasting plasma insulin which were analyzed correspondingly. Screening for mutation of PPARγ2 gene was performed by polymerase chain reaction and Pro12Ala polymorphism was analyzed using Restriction Fragment Length Polymorphism. Among controls, 89.3% were Pro/Pro homozygotes and 10.7% Ala/Ala homozygotes. InT2DM 82.7% were Pro/Pro homozygotes and17.3% Ala/Ala homozygotes. No statistically significant association of Pro12Ala with Type 2 diabetes and insulin sensitivity using HOMA β and HOMA -IR was found. However, the role of Pro12Ala polymorphism may not be excluded by a negative association study.