MDM2 SNP309 and p53 codon 72 polymorphism do not affect onset-age of lung cancer in female non-smoker patients. A-B. The cumulative incidence of cancer cases in the population was plotted as a function of age of onset of lung cancer, comparing the various p53 codon 72 (A) and MDM2 SNP309 (B) genotypes. No significant differences were noted with respective to both the different p53 and MDM2 genotypes. n = 21 for Arg/Arg, n = 16 for Pro/Pro and n = 47 for Arg/Pro and n = 22 for T/T, n = 19 for G/G and n = 54 for G/T.