Elevation of promoter methylation is a significant risk factor of type 2 diabetes in the Chinese population.

The present study aimed to investigate the contribution of DNA methylation of the protein tyrosine phosphatase, non-receptor type 1 () gene to the susceptibility to type 2 diabetes (T2D). Peripheral blood mononuclear cells (PBMCs) were collected from 97 patients with T2D and 97 age- and gender-matched controls. DNA methylation of the gene promoter was evaluated by bisulfite pyrosequencing. Independent sample t-tests were used to compare the differences in the promoter and other phenotypes between the patients with T2D and the controls. The results indicated a significant correlation between promoter methylation and the risk of T2D. Additionally, a breakdown analysis by gender revealed that methylation was associated with an increased risk of T2D in females. Furthermore, low-density lipoprotein (r=-0.183, P=0.046) and total cholesterol (r=-0.310, P=0.001) were inversely associated with methylation in females. In conclusion, the results indicate that elevated promoter methylation is a risk factor for T2D in the female Chinese population.