Numerous factors have been reported to influence the pathogenesis of atherosclerosis. The angiotensin I converting enzyme (ACE) gene is a candidate gene for atherosclerotic-related disease. In the present study, the association between the polymorphism of the ACE gene and peripheral arterial occlusive disease (PAOD) was investigated. Using polymerase chain reaction techniques, 100 patients (age 66.7 +/- 7.7 years) with PAOD and 100 age-matched controls were divided into the three ACE genotypes: II, ID and DD (Insertion I and Deletion D). There was no evidence of any association between ACE gene polymorphism and the presence of PAOD (odds ratio 0.759; 95% confidence interval 0.418-1.377). These results indicate an absence of association between DD genotype and PAOD. Further evaluation in a larger population study is required to examine the possibility of an increased risk of PAOD in DD homozygotes.