The -675 4G/5G polymorphism in plasminogen activator inhibitor-1 gene is associated with risk of asthma: a meta-analysis.

BACKGROUND

A number of studies assessed the association of -675 4G/5G polymorphism in the promoter region of plasminogen activator inhibitor (PAI)-1 gene with asthma in different populations. However, most studies reported inconclusive results. A meta-analysis was conducted to investigate the association between polymorphism in the PAI-1 gene and asthma susceptibility.

METHODS

Databases including Pubmed, EMBASE, HuGE Literature Finder, Wanfang Database, China National Knowledge Infrastructure (CNKI) and Weipu Database were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the dominant model, recessive model, codominant model, and additive model.

RESULTS

Eight studies involving 1817 cases and 2327 controls were included. Overall, significant association between 4G/5G polymorphism and asthma susceptibility was observed for 4G4G+4G5G vs. 5G5G (OR = 1.56, 95% CI 1.12-2.18, P = 0.008), 4G/4G vs. 4G/5G+5G/5G (OR = 1.38, 95% CI 1.06-1.80, P = 0.02), 4G/4G vs. 5G/5G (OR = 1.80, 95% CI 1.17-2.76, P = 0.007), 4G/5G vs. 5G/5G (OR = 1.40, 95% CI 1.07-1.84, P = 0.02), and 4G vs. 5G (OR = 1.35, 95% CI 1.08-1.68, P = 0.008).

CONCLUSIONS

This meta-analysis suggested that the -675 4G/5G polymorphism of PAI-1 gene was a risk factor of asthma.