Stratified meta-analysis by ethnicity revealed that ADRB3 Trp64Arg polymorphism was associated with coronary artery disease in Asians, but not in Caucasians

BACKGROUND: Previous studies demonstrated that ADRB3, beta-3 adrenergic receptor, participated in lipolysis and thermogenesis in adipose tissue. Consequently, this gene has attracted an increasing number of genetic studies examining its association with coronary artery disease (CAD) in different ethnicities in recent years, but no conclusion has been reached so far. The aim of this study was to explore whether the well-studied locus ADRB3 Trp64Arg in this gene confers a race-specific effect to CAD by conducting a stratified meta-analysis involving 15 independent studies and 11,802 subjects. METHODS: Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of association. Publication bias was quantified and examined with Begg's funnel plot test and Egger's linear regression method. The overall meta-analysis or stratified meta-analysis by ethnicity was performed by using STATA 12.0 software. RESULTS: A total of 15 eligible studies involving 5779 CAD cases and 6023 health controls were included in this meta-analysis. The pooled results indicated that ADRB3 Trp64Arg polymorphism was significantly associated with an increased risk of CAD. Further stratified analysis by ethnicity revealed that ADRB3 Trp64Arg polymorphism was significantly associated with CAD in Asians (allelic: OR = 1.48, 95%CI 1.13–1.94, P = .005; homozygous: OR = 2.66, 95%CI 1.87–3.77, P < .001; recessive: OR = 2.46, 95%CI 1.74–3.47, P < .001), but not in Caucasians (allelic: OR = 1.09, 95%CI 0.93–1.27, P = .290; homozygous: OR = 1.31, 95%CI 0.61–2.86, P = .490; recessive: OR = 1.31, 95%CI 0.60–2.84, P = 2.494). CONCLUSIONS: This meta-analysis suggests that ADRB3 Trp64Arg polymorphism confers a race-specific effect to CAD.