SEX HORMONE BINDING GLOBULIN GENE POLYMORPHISM AND RISK OF TYPE2 DIABETES MELLITUS IN EGYPTIAN MEN

Abstract

Conditions of hypoandrogenism in men have been linked to insulin resistance, suggesting that alterations in normal sex steroid physiology could play a role in the pathogenesis of type 2 diabetes (T2DM). Sex hormone binding globulin gene polymorphisms may be the cause of sex steroid alteration The aim of this work to study effect of sex hormone binding globulin (SHBG) gene polymorphisms on type 2 diabetes mellitus risk through its impact on testosterone and estradiol level in Egyptian men. In 185 diabetic men and 120 matched healthy controls, two polymorphisms (rs6257 and rs6259) of the gene encoding sex hormone–binding globulin were genotyped and serum levels of sex hormone–binding globulin, testosterone and estradiol were measured by ELISA; Our results showed significant decrease in sex hormone binding globulins in type 2 diabetic patients compared with the control group. Carrier of variant allele of SHBG single nucleotide polymorphism (SNP) rs6259 had a higher level of SHBG in serum (p=0.000) While carrier of SHBG rs6257 SNP had a lower level of SHBG level in serum SHBG gene polymorphisms are associated with risk of type 2 diabetes in Egyptian men, through lowering circulating levels of sex hormone–binding globulin and consequently lowering testosterone and elevating estradiol level. SHBG rs6257 genotype may have a predictive value of developing type II diabetes mellitus
Key words: Diabetes mellitus, SHBG, gene polymorphism, testosterone, and estradiol.