To confirm the p53 status of the tumours we used single-strand conformational polymorphism analysis and direct sequencing to determine that the pxn100 tumour had a wild-type p53 sequence and the pxn65 tumour had an insertion of GTGGTGAG and a deletion of base pair 868 in codon 290 (exon 8) of p53 (data not shown). The gene discussed is TP53; the disease is neoplasm.