IL4 and asthma: Subgroup analysis by ethnicity revealed no significant results in the Asian population (OR = 1.28, 95% CI = 0.24–6.80); however, the TT genotype of IL-4-590C > T significantly increased the susceptibility to asthma in the Caucasian population (OR = 1.43, 95%CI = 1.03–1.98) (Figure 3(a)).