Genotyping of p53KO/Tax Tg mice. p53 primers distinguish between WT and mutant p53 alleles with PCR products of 450 and 650 bp in size (top), respectively. Middle panel shows the detection of Tax DNA (534 bp), and the bottom panel shows PCR control detecting cell endogenous GAPDH gene (220 bp). Mut, mutant ; WT, wild type. Tax, p53, and GAPDH signals are as indicated.