Abstract:Aim To investigate the association between coronary heart disease (CHD) and heme oxygenase-1 (HO-1) promoter region (GT)n repeated sequence polymorphism and the influence of the level of serum bilirubin. Methods The polymorphism of HO-1 gene in 337 CHD patients and 240 health controls was analyzed by polymerase chain reaction-native polyacrylamide gel electrophoresis,and the level of serum bilirubin of each patient at the same time was detected. Results The HO-1 genotypes were classified into three groups:LL,LS and SS. The LL genotypic frequency and L allele frequency in CHD patients was significantly higher than control group (P<0.05); the L allele frequency had different distribution in single,double and multivessel disease (P<0.05),and the LL genotypic frequency of multivessel disease patients was higher than that of single and double vessel disease patients (P<0.05); bilirubin level of LL genotype patients was significantly lower than that of SS genotype patients (P<0.001). Conclusions The polymorphism of HO-1 promoter region (GT)n repeated sequence plays an important role in CHD pathobiology process,L allele frequency is a risk factor of CHD,which maybe correlate with its potential ability to decrease the serum bilirubin.