title: Association between alpha-1-antichymotrypsin polymorphism and susceptibility to chronic obstructive pulmonary disease.
abstract: BACKGROUND
  The antiproteases, including alpha-1-antitrypsin, are supposed to prevent lungs from becoming emphysematous. Genetic susceptibility to smoking injury may confer a risk for the development of chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  We have investigated the association between the polymorphism of alpha-1-antichymotrypsin (AACT), one of the antiproteases, and susceptibility to the development of COPD among heavy smokers. Blood samples obtained from both patients with COPD (n = 53) and control subjects (n = 65) at the Tokyo University Hospital, the Juntendo University Hospital and the Tokyo Kenbikyoin Clinic were used for this genotyping assay. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were performed to genotype the AACT biallelic polymorphism in the signal peptide (-15 alanine to threonine), and the two polymorphisms of the exon (Pro229Ala and Leu55Pro).
  
  
  RESULTS
  The proportion of AACT/Ala-15 homozygotes was significantly higher in the COPD patients than in the control subjects (COPD 37.7% vs. control 18.5%). The odds ratio for AACT/Ala-15 homozygotes vs. all other genotypes was 2.7 (95% CI 1.2-6.2) for the COPD group. We could not find any association between the other two polymorphisms and COPD.
  
  
  CONCLUSIONS
  Genetic polymorphism in the signal peptide of AACT may be associated with individual susceptibility to the development of COPD, because the AACT/Ala-15 genotype is predominantly found in patients with COPD. It is suggested that AACT/Ala-15 genotype may be less protective against smoking injury.
authors.affiliation: Department of Geriatric Medicine, University of Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ishii
authors.forename: T
authors.initials: T
authors.lastname: Matsuse
authors.forename: S
authors.initials: S
authors.lastname: Teramoto
authors.forename: H
authors.initials: H
authors.lastname: Matsui
authors.forename: T
authors.initials: T
authors.lastname: Hosoi
authors.forename: Y
authors.initials: Y
authors.lastname: Fukuchi
authors.forename: Y
authors.initials: Y
authors.lastname: Ouchi
mesh_terms: D000328:Adult; D000409:Alanine / Q000235:genetics; D000483:Alleles; D019943:Amino Acid Substitution; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000201:enzymology / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D011392:Proline / Q000235:genetics; D021382:Protein Sorting Signals / Q000235:genetics; D000514:alpha 1-Antichymotrypsin / Q000097:blood / Q000235:genetics*
chemical_list: D021382:Protein Sorting Signals; D000514:alpha 1-Antichymotrypsin; D011392:Proline; D000409:Alanine