Transforming growth factor-beta1 genotype and susceptibility to chronic obstructive pulmonary disease.
BACKGROUND
Only a few long term smokers develop symptomatic chronic obstructive pulmonary disease (COPD) and this may be due, at least in part, to genetic susceptibility to the disease. Transforming growth factor beta1 (TGF-beta1) has a number of actions that make it a candidate for a role in the pathogenesis of COPD. We have investigated a single nucleotide polymorphism at exon 1 nucleotide position 29 (T-->C) of the TGF-beta1 gene that produces a substitution at codon 10 (Leu-->Pro).


METHODS
The frequency of this polymorphism was determined in 165 subjects with COPD, 140 healthy blood donors, and 76 smokers with normal lung function (resistant smokers) using the polymerase chain reaction and restriction enzyme fragment length polymorphism.


RESULTS
The distribution of genotypes was Leu-Leu (41.8%), Leu-Pro (50.3%), and Pro-Pro (7.9%) for subjects with COPD, which was significantly different from the control subjects (blood donors: Leu-Leu (29.3%), Leu-Pro (52.1%) and Pro-Pro (18.6%), p=0.006; resistant smokers: Leu-Leu (28.9%), Leu-Pro (51.3%) and Pro-Pro (19.7%), p=0.02). The Pro10 allele was less common in subjects with COPD (33%) than in blood donors (45%; OR=0.62, 95% CI 0.45 to 0.86, p=0.005) and resistant smokers (45%; OR=0.59, 95% CI 0.40 to 0.88, p=0.01).


CONCLUSIONS
The proline allele at codon 10 of the TGF-beta1 gene occurs more commonly in control subjects than in individuals with COPD. This allele is associated with increased production of TGF-beta1 which raises the possibility that TGF-beta1 has a protective role in COPD.
Wu
L
L
Department of Molecular Medicine, University of Auckland, Auckland, New Zealand.
Chau
J
J
Young
R P
RP
Pokorny
V
V
Mills
G D
GD
Hopkins
R
R
McLean
L
L
Black
P N
PN
D000328:Adult; D000368:Aged; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic / Q000235:genetics; D029424:Pulmonary Disease, Chronic Obstructive / Q000235:genetics*; D012044:Regression Analysis; D012907:Smoking / Q000503:physiopathology; D016212:Transforming Growth Factor beta / Q000235:genetics*; D053773:Transforming Growth Factor beta1
C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1