This suggested that the individuals with the haplotypes AAG (PPARGC1A gene) and CTCG (UCP1 gene) have higher susceptibility to IFG or T2DM, while those with haplotypes of AAG (PPARGC1A gene) and CTCA (UCP1 gene) have lower susceptibility to IFG or T2DM. Here, UCP1 is linked to type 2 diabetes mellitus.