Abstract: The study is to investigate whether the insertion/deletion polymorphism of angiotensin 1 converting enzyme(ACE)gene is associated with Type 2 diabetes mellitus without cardiovascular complications(DM2)and that with myocardial infarction(MI)in Chinese, and to ascertain the interaction of serum ACE levels and ACE gene polymorphism to the development of the associated diseases. ACE genotypes of 82 cases with MI, 86 with DM2 and 84 controls were determined by polymerase chain reaction(PCR). Serum ACE levels were measured with ultraviolet photometry. The increased frequencies of D allele(0.52)and DD genotype(0.32)were respectively observed in 82 subjects with MI compared with 84 control subjects(0.36,0.15 respectively, P<0.05). The odds ratio associated with DD/II genotype was 3.01(95%CI 1.28～7.04, P<0.01)for MI. Individuals with DD genotype had the highest serum ACE in all groups, and with II genotype the lowest levels. There was no difference in allele distribution between 86 DM2 patients and the controls. ACE gene polymorphism is associated with serum ACE levels(r= 0.65, P<0.01). Deletion polymorphism of the ACE gene contributes to the development of myocardial infarction and is a risky factor for MI in Chinese type 2 diabetes.

Key words: angiotensin-converting enzyme, gene polymorphism, aged type 2 diabetes mellitus, myocardial infarction