title: [Polymorphism of angiotensin-converting enzyme gene and susceptibility to asthma with familial aggregation].
abstract: OBJECTIVE
  Angiotensin-converting enzyme (ACE) plays a key role in the metabolism of angiotensin II (AT II) and inactivation of bradykinins and tachykinins, which are potent bronchial constrictors and mediators of inflammation asthma, and ACE is heavily expressed in the lungs. An insertion-deletion (D/I) polymorphism of ACE gene has been shown to be associated with levels of ACE. Whether or not the polymorphism of ACE gene is associated with asthma and bronchial responsiveness was investigated.
  
  
  METHODS
  A case-control study was carried out in 50 asthmatics, 7 families with at least 2 asthmatic individuals, and 50 healthy subjects. The insertion/deletion (I/D) polymorphism of ACE gene was amplified by polymerase chain reaction (PCR). Methacholine broncho(Mch)-provocation and pulmonary function tests were performed in all asthmatics.
  
  
  RESULTS
  There was an higher gene frequency of DD genotype of ACE gene in asthmatic subjects and families individuals compared with healthy subjects (46% vs 16%, P < 0.05; Odd ratio 4.98). Accordingly, the mean values of FEV1% and FEV1/FVC were higher in asthmatics carrying non-DD alleles than patients with DD genotype (74% vs 57%, P < 0.05; 79% vs 69%, P < 0.05, respectively).
  
  
  CONCLUSIONS
  The results suggested that DD allele of ACE genotype was significantly involved in genetic susceptibility to asthma. DD genotype of ACE might be a risk factor for the degree of airway obstruction.
authors.affiliation: Department of Respiratory Disease, Peking Union Medical College Hospital, CAMS & PUMC, Beijing 100730.
authors.forename: J
authors.initials: J
authors.lastname: Gao
authors.forename: Y
authors.initials: Y
authors.lastname: Lin
authors.forename: Y
authors.initials: Y
authors.lastname: Xiao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000235:genetics*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D005819:Genetic Markers; D007703:Peptidyl-Dipeptidase A