The role of genetic polymorphism of β3-adrenergic receptor in the susceptibility to diabetes and its related disorders: a case–control study on Egyptian population

Background The β3-adrenergic receptor (β3-AR) is mainly expressed in adipose tissue and plays an important role in lipid metabolism and metabolic rate by mediating lipolysis and thermogenesis. It has been suggested that the Trp64Arg (T→C) polymorphism in the β3-AR gene affects fat accumulation and/or impairment of lipid and carbohydrate metabolism. Objective The aim of this study was to investigate whether common polymorphism (Trp64Arg) of β3-AR gene has a role in the apparent susceptibility to type 2 diabetes mellitus (DM) and its related disorders in the Egyptian population. Patients and methods One hundred and thirty five healthy controls and 123 individuals with type 2 DM were enrolled in the study. The β3-AR Trp64Arg polymorphism was identified using restriction fragment length polymorphism PCR of peripheral blood DNA samples. Analysis of data was performed using SPSS program 11. Results Allele frequency for C was 23.2% in the diabetic group compared with 12.2% in the control group. The carriers of XC genotype (TC and CC) were at high risk of developing type 2 DM (odds ratio=2.8; 95% confidence interval=1.6–4.9) when compared with the carrier of TT genotype. Furthermore, they were at much higher risk of developing its related disorders such as central obesity, dyslipidemia, and hypertension (odds ratio=2.8; 1.8, 1.5, 2.2, and 2.7 for BMI, waist–hip ratio, triglycerides, high-density lipoprotein, and hypertension, respectively). Conclusion The prevalence of Arg64 allele of the Trp64Arg polymorphism in the β3-AR gene is a risk factor for type 2 DM and its related disorders in the Egyptian population.