SCREENING PATIENTS FOR HETEROZYGOUS-P53 MUTATIONS USING A FUNCTIONAL ASSAY IN YEAST

Inherited mutations of the p53 gene significantly increase the risk of developing diverse malignancies, and germline p53 mutations can be de tected by assaying the transcriptional activity of the p53 protein in mammalian cells. Here we describe a method starting with lymphocytes t hat allows detection of germline p53 mutations by 'functional' analysi s of p53 protein expressed in Saccharomyces cerevisiae. The p53 PCR pr oducts are directly cloned into yeast expression vectors in vivo and s ubsequently tested for transcriptional activity in a simple growth ass ay. This technique, functional analysis of separated alleles in yeast (FASAY), requires only a few steps, can be automated readily and shoul d permit screening for germline or somatic heterozygous mutations in a ny gene whose function can be monitored in yeast.