The codon 64 polymorphism of the β 3-adrenergic receptor gene is not associated with coronary heart disease or insulin resistance in nondiabetic subjects and non-insulin-dependent diabetic patients

Abstract

Hyperinsulinemia has been shown to predict coronary heart disease (CHD) events in both nondiabetic subjects and patients with non-insulin-dependent diabetes mellitus (NIDDM). Therefore, defects in genes that regulate insulin action could be responsible for an increased risk of CHD. The Trp64Arg polymorphism of the β 3-adrenergic receptor gene has been linked with abdominal obesity, insulin resistance, and early-onset NIDDM. Therefore, we screened for this polymorphism among 185 unrelated nondiabetic subjects (101 men and 84 women; age, 56 ± 1 years [mean ± SEM]; body mass index [BMI], 27.8 ± 0.3 kg/m 2) with angiographically confirmed CHD (stenosis > 50% in ≥ two coronary arteries), among 119 unrelated patients with NIDDM (90 men and 29 women; age, 62 ± 1 years; BMI, 28.7 ± 0.4 kg/m 2; 95 had CHD by the same criteria and 24 had definite myocardial infarction [MI]), and among 82 healthy men (age, 54 ± 1 years; BMI, 26.3 ± 0.4 kg/m 2) from our previous study. The frequency of the Trp64Arg allele of the β 3-adrenergic receptor gene was similar in nondiabetic patients with CHD (8%), NIDDM patients with CHD (7%), and nondiabetic subjects without CHD (7%). No association was found between cardiovascular risk factors and the codon 64 polymorphism of the β 3-adrenergic receptor gene in patients with CHD. Similarly, this polymorphism was not significantly related to insulin resistance in nondiabetic and NIDDM subjects with CHD evaluated by the euglycemic clamp technique. These results indicate that the Trp64Arg allele of the β 3-adrenergic receptor gene does not contribute to the risk of CHD in nondiabetic subjects and NIDDM patients.