Meta-Analyses of KIF6 Trp719Arg in Coronary Heart Disease and Statin Therapeutic Effect

AIMS The goal of our study is to assess the contribution of KIF6 Trp719Arg to both the risk of CHD and the efficacy of statin therapy in CHD patients. METHODS AND RESULTS Meta-analysis of 8 prospective studies among 77,400 Caucasians provides evidence that 719Arg increases the risk of CHD (P<0.001, HR = 1.27, 95% CI = 1.15-1.41). However, another meta-analysis of 7 case-control studies among 65,200 individuals fails to find a significant relationship between Trp719Arg and the risk of CHD (P = 0.642, OR = 1.02, 95% CI = 0.95-1.08). This suggests that the contribution of Trp719Arg to CHD varies in different ethnic groups. Additional meta-analysis also shows that statin therapy only benefit the vascular patients carry 719Arg allele (P<0.001, relative ratio (RR) = 0.60, 95% CI = 0.54-0.67). To examine the role of this genetic variant in CHD risk in Han Chinese, we have conducted a case-control study with 289 CHD cases, 193 non-CHD controls, and 329 unrelated healthy volunteers as healthy controls. On post hoc analysis, significant allele frequency difference of 719Arg is observed between female CHD cases and female total controls under the dominant model (P = 0.04, χ(2) = 4.228, df = 1, odd ratio (OR) = 1.979, 95% confidence interval (CI) = 1.023-3.828). Similar trends are observed for post hoc analysis between female CHD cases and female healthy controls (dominant model: P = 0.04, χ(2) = 4.231, df = 1, OR = 2.015, 95% CI = 1.024-3.964). Non-genetic CHD risk factors are not controlled in these analyses. CONCLUSIONS Our meta-analysis demonstrates the role of Trp719Arg of KIF6 gene in the risk of CHD in Caucasians. The meta-analysis also suggests the role of this variant in statin therapeutic response in vascular diseases. Our case-control study suggests that Trp719Arg of KIF6 gene is associated with CHD in female Han Chinese through a post hoc analysis.