Figure 2.

Autoradiographs from part of the sequence of TP53 exon 6 in selected oral squamous cell carcinomas. Lanes are grouped together for the individual tumours to facilitate the identification of abnormal mutant bands (four tumours are shown in (A), and seven tumours are shown in (B)). (A) Shows a C to T transition at codon 213 in lane 3 (arrow). This mutation changed a codon that encodes arginine into a stop codon; no tumour cells in this carcinoma stained for p53 (table 2; T19). (B) Shows an A to G transition at codon 193 in lane 4 (arrow). This mutation results in a histidine to arginine change and the carcinoma showed p53 immunostaining in more than 75% of the tumour cells (table 2; T46).