It is worth noting that our results are consistent with a previous meta-analysis conducted by Xu et al.[73], who analyzed associations between T2DM and UCP2 Ala55Val, UCP2 -866G/A and UCP3 -55C/T polymorphisms in 17 studies, but did not analyze neither the UCP1 -3826A/G and UCP2 Ins/Del polymorphisms nor the allele contrast or co-dominant inheritance models. Here, UCP1 is linked to type 2 diabetes mellitus.