Associations of IL-2 and IL-4 gene polymorphisms with psoriasis in the Korean population

BACKGROUND: Psoriasis is association with an overexpression of T-helper cell type 1(Th1) cytokines and relative underexpression of Th2 cytokines. The cytokine production is under genetic control, and certain allelic variants of cytokine genes are associated with higher or lower cytokine production in vitro and in vivo. OBJECTIVES: We aimed to evaluate association of cytokine genes polymorphisms with psoriasis in the Korean population. METHODS: We investigated the polymorphisms of IL-2 -330, IL-4 -590, IL-4 receptor +1902, IL-10 -1082 and -819, and IFN-gamma intron 1 in 114 psoriasis patients and 281 healthy normal controls in Korean. RESULTS: IL-2 -330*G and IL-4 -590*C alleles significantly increased in psoriasis patients, especially late-onset group, compared to the control. The combined effect of IL-2 -330*G and IL-4 -590*C showed that the positive combination of IL-2 -330*G and IL-4 -590*C alleles were more significantly associated with the late-onset group of psoriasis patients than the controls. CONCLUSIONS: These results suggest that the genetic polymorphisms of IL-2 and IL-4 genes can be susceptible to psoriasis in Korean, especially late-onset psoriasis group.