IL4 and Alzheimer disease: Comparing to the haplotype CCT composed of IL-4 rs2243283, rs2243250 and rs2243248, the frequency of haplotype GTT in AD patients was significantly lower than that in controls (GTT vs. CCT: P = 0.011, OR = 0.65, 95% CI = 0.47–0.90) (Table 5).