DD genotype of angiotensin-converting enzyme may be a risk factor for development of asthma in children

Objective The insertion/deletion polymorphism of angiotensin-converting enzyme (ACE) gene in intron 16 of a 287 bp nonsense domain was identified and shown to be closely associated with the levels of ACE in plasma and cells. ACE is heavily expressed in the lung and plays a key role in the metabolism of angiotensin II and inactivation of bradykinin peptides and substance P, which are potent bronchial constrictors and inflammatory mediators of asthma. The present study was conducted to assess the relationship between the insertion/deletion polymorphism of ACE gene and asthma in children. Methods ACE genotypes were determined by polymerase chain reaction (PCR) in 52 asthmatic children, 54 children with pneumonia and 40 healthy controls. The peak expiratory flow rate (PEFR) was determined to evaluate the lung function of 23 asthmatic children. Results The ACE genotype (II, ID and DD) distribution was significantly different among the three groups (P 0.05) . Conclusion DD genotype of ACE gene may be related to susceptibility of children to asthma and may be a risk factor in development of asthma. Key words: Asthma; Peptidyl-dipeptidase A; Polymorphism (genetics); Genotype