Subgroup analyses found that the IL4RA I50V polymorphism was significantly associated with asthma risk in Asians (OR = 1.72, 95% CI 1.31-2.25, P<0.0001), pediatric asthma risk (OR = 1.50, 95% CI 1.13-1.99, P = 0.005), and atopic asthma risk (OR = 1.88, 95% CI 1.27-2.79, P = 0.002).
To verify the association of transforming growth factor-beta1(TGF-beta1) (C-509T and T869C), CD14 (C-159T), IL-4 (C-590T), IL-4R (ILe50Val) and ADAM33 (S_2) gene polymorphisms with asthma severity in a sample of patients with mild, moderate and severe persistent atopic asthma.
The objective of this study was to replicate this association and confirm the possible role of the Ile50Val polymorphism of IL4R in the etiology of atopic asthma in a Japanese population.