SIRT2 and type 2 diabetes mellitus: In this study, we aimed to detect the novel SNP mutation in the SIRT2 gene promoter region in the Chinese population, and to investigate the effects of the SNP haplotype combinations on the promoter activity and clinical characteristics of T2D patients, and finally to elucidate the molecular mechanism of the genetic variation, which may provide convincing evidence for the extensive usage of haplotypes.