The tumour suppressor gene,TP 53(commonly also calledp53) has multiple, important cellular functions involving control of apoptosis, downstream cell cycle regulation via p21 and cyclin dependent kinases, and control of tumour angiogenesis. Somatic mutation ofTP 53is considered to be the most common genetic mutation in human cancer. Mutations of the gene are associated with drug resistance and poor patient prognosis in human cancers. Immunohistochemistry to detect mutatedTP 53is unreliable and molecular biology approaches are therefore preferable for its assessment. This chapter describes protocols for the ‘gold standard’, but perhaps complex and time consuming, methods for sequencingTP 53, by cDNA and genomic based sequencing techniques.
