[Gene polymorphisms of rennin-angiotensin system and coronary artery thrombosis disease].

To investigate the distribution frequencies of angiotensin-converting enzyme (ACE), angiotensinogen (AGT), angiotensin II I type receptor (AT1R) genotypes in Chinese, to find the relationships between polymorphisms of ACE, AGT and AT1R gene, and coronary artery thrombosis disease (CATD) and to study the interactions of themselves, PCR and PCR-RFLP techniques were performed to determine the genotypes of ACE, AGT and AT1R gene in CATD group (192 cases) and control group (110 cases). The results showed that (1) genotype frequencies of the three polymorphisms in the control group were 12.2% (DD), 43.9% (ID), and 43.9% (II) for the ACE I/D polymorphism; 8.2% (MM), 36.7% (MT), and 55.1% (TT) for AGT M235T polymorphism; 91.8% (AA), 8.2% (AC) for AT1R A1166C polymorphism respectively; (2) there were no significant differences between patients in either the control group, the non-MI group, or the MI group in any genotype frequency of all these three genes (P >0.05). (3) the odds ratio for CATD in subjects carrying both AT1R-AC and AGT-TT genotype was 3.517 (95% CI 0.988 - 12.527), compared with those carrying AT1R-AA and AGT-TT genotype and was 15.000 (95% CI 1.940-115.963), compared with those carrying AT1R-AC and AGT-MM/MT genotype. In subjects with AT1R-AC genotype, there was also a great difference of ACE D allele frequency between control group and CATD group (P=0.017). It is concluded that genotype frequencies of ACE I/D polymorphism, AGT M235T polymorphism, and AT1R A1166C polymorphism were obviously different from those in western countries. Although these three polymorphisms were not independent risk factors for CATD or myocardial infarction (MI) in Chinese, AT1R-AC genotype has a significant synergistic effect with AGT-TT genotype. There is also a obvious interaction between AT1R-AC genotype and ACE D allele.