Polymorphisms of PHF11 and DPP10 are associated with asthma and related traits in a Chinese population.

Background: Initial studies by positional cloning have identified the genes encoding the plant homeodomain zinc finger protein 11 (PHF11) and dipeptidyl-peptidase 10 (DPP10) as asthma susceptibility genes. The variants in the two genes have been associated with asthma in several populations of European or Latin American origin.

Objective: The aim of this study was to assess the common PHF11 and DPP10 polymorphisms for associations to asthma and asthma-related traits in a Han Chinese population.

Methods: We genotyped six polymorphic markers in PHF11 and five polymorphic markers in DPP10 in a Han Chinese case-control cohort consisting of 408 asthma patients and 288 unrelated disease-free controls recruited from the Northern region of China. We analyzed the association between these markers and asthma as well as a number of intermediate, asthma-related traits. Linkage disequilibrium and haplotype patterns were also evaluated.

Results: Significant associations were identified between two makers in PHF11 (rs1046295 and rs16659) and asthma susceptibility (odds ratio, OR = 1.32, 95% con fidence interval, CI = 1.06-1.65, p = 0.0096, for rs1046295, and OR = 1.41, 95% CI = 1.12-1.75, p = 0.0026, for rs16659). A strong association was observed between an SNP in DPP10 (rs10208402) and log(e)-transformed total IgE (p = 0.0003) and the percentage of peripheral blood eosinophils (p = 0.0023). A weak association between rs1430090 in DPP10 and forced expiratory volume in 1 s was also observed (p = 0.048). Haplotype analysis revealed two protective haplotypes in PHF11 against asthma.

Conclusion: The results provide supporting evidence for genetic variants in PHF11 and DPP10 genes underlying asthma susceptibility and asthma-related quantitative traits in a Han Chinese population.