Association of Angiotensin-converting Enzyme Gene Polymorphism with Susceptibility to Asthma Disease in Western Iran

Asthma is a complex disease caused by a combination of multiple genetic and environmental factors. Angiotensin-converting enzyme (ACE) is involved in the pathogenesis of asthma by inactivating bradykinin, substance P, and neurokinin A. It has been shown that the level of ACE variation in serum is associated with an insertion-deletion (I/D) polymorphism. So, this study aimed to investigate the association of these polymorphisms with asthma in western Iran. In this case-control study, 111 asthmatic patients as a case group and 80 healthy subjects as a control group were evaluated. The ACE gene polymorphism was determined by the PCR method. The relationship between genotypes done by the χ2 test and the relative risk of disease with genetic polymorphism (Odds Ratio) was performed using logistic regression. The frequency of I/D genotypes (included in II, ID, and DD) between patient and control groups had no significant difference. In addition, none of the genotypes in the patient and control groups show any significant differences between men and women. However, the frequency of ID and DD genotypes was considerably different between the male patient groups (over and under 40 years old). Hence, these genotypes are suggested to be a risk factor for asthma. The results of our study indicate that ACE gene polymorphism is not significantly associated with asthma in the west of Iran.