Objective To determine the relationships of Met416Val and XbaI polymorphism of muscle glycogen synthase (GYS1) gene and Trg64Arg variant of the β 3 adrenergic receptor (β 3 AR) gene with type 2 diabetes mellitus (DM) and its intermediate phenotypes in the Chinese population Methods Polymerase chain reaction oligonucleotide ligation assay and restriction fragment length polymorphism assay were used to evaluate the GYS1 and β 3 AR gene polymorphisms in 102 pairs of case control Chinese spouses Results Subjects with Met416Val variant had a significantly higher 2 hour post glucose level than subjects without this variant had in diabetic group ( P =0 032) The Met416Val polymorphism of GYS1 gene was not significantly associated with the risk of type 2 DM (adjusted OR=1 67; 95% CI: 0 73-3 81, P =0 223) Subjects with Trp64Arg variant had a significantly higher serum uric acid level than subjects without this variant had in diabetic group ( P =0 034) The combination of BMI and Arg64 allele carrier of the β 3 AR gene increased the diabetic risk over four fold (adjusted OR=4 00; 95%CI: 1 53-10 45, P =0 005) Conclusions In the Chinese population, Met416Val polymorphism is identified in a subgroup of diabetic subjects with high 2 hour post glucose It will explain why some diabetic patients appear to be genetically predisposed to developing high postpradial glucose level The presence of the Arg64 allele in the β 3 AR gene may predispose patients to higher serum uric acid level