Estimation of TGF-β1 genotypes in Egyptian smokers; association with FEV(1) in COPD patients

INTRODUCTION: TGF-β1 is a cytokine with many different effects on cell proliferation, differentiation and inflammation and can protect against the development of COPD. This work aims to study the association between COPD and the TGF-β1 gene genotypes. MATERIAL AND METHODS: The study included 70 males: 25 smokers with COPD, 25 resistant smokers, and 20 normal non-smokers as the control. They were subjected to spirometry pre- and post-bronchodilator (FEV(1), FEV(1)/FVC), estimation of serum level of TGF-β1 gene by PCR and RFLP. RESULTS: The percent of Pro-Leu was 28% in the COPD group, 84% in the resistant smokers group and 85% in the control group. There was a highly significant statistical difference in FEV(1)% of predicted associated with the distribution of TGF-β1 gene genotypes: 56.9 ±8.4% with Pro-Leu genotype and 35.5 ±8.8% with Leu-Leu genotype in COPD patients, 93.2 ±6.2% with Pro-Leu genotype and 86.7 ±0.9% with Leu-Leu genotype in the resistant smokers group. CONCLUSIONS: The Pro-allele genotype is associated with increased production of TGF-β1, which has a protective role against the development of COPD and is important in preserving the decline of FEV(1) in COPD patients.