After excluding SNPs with P-HEIDI < 0.05 and FDR-adjusted P-values > 0.05 via SMR analysis, we identified a total of 18 genes that have a causal relationship with lung cancer, including U919328.19, GABBR1, IER3, LINC00243, SKIV2l, HLA-DQA1, HLA-DQB1, HLA-DQB1-AS1, HLA-DQB2, RNASET2, RP1-167A14.2, PSMD5-AS1, MPZL2, MPZL3, PSMA4, UCKL1 and PRPF6. The gene discussed is PSMA4; the disease is lung cancer.