Abstract
Background
Angiotensin I-converting enzyme gene has three genotypes, I/I, I/D, D/D, as a result of the insertion/deletion polymorphism of 287 bp in the region of intron 16. As polymerase chain reaction(PCR) has been used for detection of this genetic polymorphism, many reports about this genetic polymorphism have been published for the last 3years. However, there was no report about this subject in Korea. We performed this study to analyze the pattern of insertion / deletion polymorphism of angiotensin I-converting enzyme gene in the normal Korean people and patients with various ischemic heart diseases.
Methods
We studied 169 patients who received coronary angiography. Group 1 is normal control group(n=68) which consists of people whose coronary angiograms are normal. Group 2 is stable angina group(n=24). Group 3 is acute ischemic syndrome group(n=77) which consists of unstable angina patients(n=28) and myocardial infarction patients(n=49). In each subject, following data were obtained : body mass index, serum total cholesterol, LDL cholesterol, HDL cholesterol, VLDL cholesterol, triglyceride, LP(a), apolipoprotein A1, and apolipoprotein B level. Genomic DNA was extracted from the mononuclear cells of each subject and PCR was performed using new primers that were optimized by us for the region of intron 16 and exon 17. Amplified fragments were confirmed by DNA sequencing.
Results
Genotype frequency of normal control group is as follows. D/D : I/D : I/I=14.7% : 50.5% : 35.3%, D allele : I allele=0.397 : 0.603. The frequency of I allele significantly higher than that of Caucasians(p<0.05), and quite similar to that of Japanese. Neither the genotype frequencies of group 2 nor group 3 was significantly different from that of normal control group. In group 3 of acute ischemic syndrome, patients whose serum cholesterol level is lower than 200mg/dl has significantly higher D allele frequency than patients whose serum cholesterol level is higher than 200mg/dl(48.5% vs 28.8%, p<0.05).
Conclusions
Genotype frequency of angiotensin I-converting enzyme gene polymorphism of normal Korean people is different from that of Caucasians, and quite similar to that of Japanese. D allele is associated with the development of acute ischemic syndrome in the patients whose serum lipid profile is normal.