G-protein beta3 subunit gene C825T polymorphism is associated with arterial hypertension in Polish patients with type 2 diabetes mellitus.

BACKGROUND

Diabetes mellitus type 2 results from a complex of hereditary and environmental factors. Genes encoding elements of the G-protein system are candidate genes in hypertension and obesity. Since insulin uses G-sensitive mechanisms to enhance tissue glucose uptake and vasodilatation, the GNB3 gene may be a candidate gene in type 2 diabetes. The goal of our research was to determine if the C825T polymorphism at the G-protein b3 subunit gene locus is associated with type 2 diabetes.

MATERIAL/METHODS: The study population consisted of 172 Polish patients with type 2 diabetes and 172 healthy, age- and sex-matched controls. The C825T polymorphism was detected by PCR and RFLP.

RESULTS

A higher frequency of genotypes containing the mutation (CT+TT) was observed among the diabetics than in the controls. The T825 variant occurred more often among hypertensive diabetics (71%) than among diabetics with normal blood pressure (42.5%). The OR for hypertension in diabetic subjects bearing CT+TT genotypes was higher than in patients with the CC genotype. Overweight and obesity were not associated with the T825 variant in either the experimental subjects or the controls.

CONCLUSIONS

In this population, the T825 variant of the GNB3 gene was not associated with type 2 diabetes itself, nor with overweight and obesity, but was associated with diabetic hypertension. Upon confirmation of our results this variant may be useful as a genetic marker of susceptibility to hypertension and vascular complications in type 2 diabetes.