IL-18 137G>C was found to be significantly associated with the risk of NPC (Allele model: OR=1.50, 95% CI = 1.30-1.73, p<0.00001, I2 = 13%, Figure 6A, Dominant model: OR=1.58, 95% CI = 1.33-1.89, p<0.00001, I2 = 2%, Figure 6B, Recessive model: OR=1.79, 95% CI = 1.24-2.60, p=0.002, I2 = 0%, Figure 6C, Heterozygote model OR=1.51, 95% CI = 1.26-1.81, p<0.00001, I2 = 0%, Figure 6D, Homozygote model OR=2.07, 95% CI = 1.42-3.02, p=0.0002, I2 = 0%, Figure 6E). Here, IL18 is linked to nasopharyngeal carcinoma.