MTHFR and lung carcinoma: Significance of the tested genes SNPs for the survival of lung cancer patients analysed with Cox model has not showed the single SNP effect, but SNPs combination of genes MDM2 T/T, MTHFR C/T (P = .14) along with the stage of patients with lung cancer (P = .02) were associated with different periods of survival of lung cancer patients (Figure 4).