Objective: Fibroblast growth factor 10 (FGF 10) signaling pathway is crucial to lung development and epithelial reconstruction. The aim of this study was to investigate the relationship between gene polymorphisms in FGF 10 and susceptibility to chronic obstructive pulmonary disease (COPD) in a Han population of North China.
Methods: The subjects included 220 patients with COPD (COPD group) and 285 healthy controls (control group). The COPD patients, admitted to our hospital from June 2007 to May 2012 because of acute exacerbation, included 142 males and 78 females, aging from 43 to 93 years [mean (74 ± 10)]. The control group included 183 males and 102 females, aging from 44 to 97 years [mean (72 ± 9)]. According to results of lung function testing, patients with COPD were divided into mild (8 cases), moderate (62 cases), and severe (48 cases) and very severe groups (102 cases). The genotype frequencies of FGF 10 gene single nucleotide polymorphisms (rs10473352, rs16873956, rs2973644, rs1011814, rs10402070 and rs723166) were genotyped by RFLP PCR-restriction fragment length polymorphism method and micro-sequencing (SnaPshot) technology assay. Chi-square test was used to perform the Hardy-Weinberg equilibrium test. Unconditional logistic of regression model was used to calculate odds ratio (OR) and 95%CI. The 2 groups were compared using t-test.
Results: The rs2973644 locus AA, GA and GG genotype frequencies in the COPD group and the control group were 108/220, 92/220, 20/220 and 167/285, 104/285, 14/285, respectively; while the frequencies of allele A and G were 308/440, 132/440 and 438/570, 132/570, respectively. The rs10473352 locus TT, TC and CC genotype frequencies in the COPD group and the control group were 142/220, 72/220, 6/220 and 202/285, 82/285, 1/285, respectively, the differences being statistically significant (χ(2) value were 6.021-6.213, P < 0.05). The rs10473352 allele T and C frequencies were 356/440, 84/440 and 486/570, 84/570, respectively, the differences being not statistically significant (χ(2) = 3.395, P > 0.05). The rs1011814 locus TT, TC and CC frequencies in mild and moderate compared with severe and very severe COPD disease were 16/68, 39/68, 13/68 and 29/150, 67/150, 54/150, respectively; while its allele T, C frequencies were 71/136, 65/136 and 125/300, 175/300, respectively; the differences being statistically significant (χ(2) values were 6.287 and 4.200, all P < 0.05). The remaining 5 tSNP (rs10473352, rs16873956, rs2973644, rs10402070 and rs723166) genotype distribution and allele frequencies were not significantly different (OR value were 0.606-1.357, P > 0.05).
Conclusions: FGF 10 gene SNP sites rs2973644 and rs10473352 polymorphisms may be associated with susceptibility to COPD in Han population of North China. The SNP in rs1011814 may be associated with severity of COPD.