Based on three independent case-control studies, we genotyped five rare SNPs in MKK7 (i.e., rs28395770G>A: p.Glu116Lys, rs56316660A>G: p.Asn118Ser, rs56106612C>T: p.Arg138Cys, rs55800262G>A: p.Ala195Thr and rs1053566 C>T: p.Leu259Phe) and investigated their associations with lung cancer risk, metastasis and prognosis. The gene discussed is MAP2K7; the disease is lung cancer.