Association between genetic polymorphism in the promoter region of heme oxygenase-1 and myocardial infarction in patients from Uighur ethnics of Xinjiang Autonomous Region / 中华急诊医学杂志

ABSTRACT

Objective To investigate the association between acute myocardial infarction (AMI) and the (GT)n repeat sequence polymorphism in promoter region of heme oxygenase-1 (HO-1) , and to study the influence of serum bilirubin on AMI as well for HO-1 as a rate-limiting enzyme of bilirubin production in patients from Uighur national minority. Method Totally 287 patients with AMI evidenced by coronary arteriography admitted from January 2006 to June 2008 were eligible for being studied, and another 190 healthy subjects without anomaly in coronary arteriography, and with normal findings in physical examination and in variety of biochemical assays were enrolled as controls. Serum total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDL-C), serum bilirubin were detected. Polymerase chain reaction-nondenaturing polyacrylamide gel electrophoresis was used to detect HO-1 promoter (GT)n repeat polymorphism, and at the same time the serum bilirubin was determined. The group representation of samples was tested with HardyWeinberg balance test. Differences in distributions of genotypes and alleles between AMI patients and control subjects were analyzed using Chi-square test. Comprehensive evaluation of the factors associated with myocardial infarction using multi-factor Logistic regression analysis. P < 0.05 was considered as significantly different. Results Body mass index, triglyceride, high density lipoprotein cholesterol and the proportion with hypertension in myocardial infarction group was significantly higher than those in control group ( P < 0.01) . The X~2 values of HO-1genotype distribution in the myocardial infarction group and the control group were 2.09 and 0.05, respectively (P > 0.05), consist with the results of Hardy-Weinberg balance test. The HO-1 genotype was classified into three groups, L/L, L/S and S/S. The L/L genotype frequency (35.5%) and L-allele frequency (57.8%) in AMI group and in control group showed statistically significant differences, respectively (X~2 = 11.65, P = 0.001; X~2= 11.32, P = 0.003). The bilirubin level of L/L genotype significantly decreased compared with that of S/S, L/S genotype ( P all < 0. 001) . Logistic regression analysis showed that body mass index, high blood pressure,triglycerides, blood bilirubin and HO-1 gene polymorphism are risk factors of myocardial infarction. Conclusions To the Xinjiang Uighur ethics, HO-1 promoter ( GT) n repeat polymorphism and the occurrence of myocardial infarction are relevant. People with L allele genotype have lower serum bilirubin and higher risk of myocardial infarction.