The pooled analysis disclosed no relevance between PD-1.1 variation and cancer risk (A vs. G: OR = 0.93, 95% CI = 0.78-1.10, P = 0.380; AA vs. GG: OR = 1.14, 95% CI = 0.89-1.47, P = 0.300; GA vs. GG: OR = 0.88, 95% CI = 0.72-1.09, P = 0.247; AA+GA vs. GG: OR = 0.88, 95% CI = 0.70-1.11, P = 0.294; AA vs. GA+GG: OR = 1.12, 95% CI = 0.93-1.34, P = 0.224, Figure 5 and Table 2). The gene discussed is PDCD1; the disease is cancer.