We report here a family with some of the characteristics of Li-Fraumeni syndrome (Li-Fraumeni-like) in which there is a 2 base pair deletion within exon 6 of TP53 in two affected individuals. Of particular interest in this family is a study of loss of heterozygosity (LOH) of the TP53 gene, and the finding that there is LOH in all cancers available for study from mutation carriers, and additionally from a benign endometrial polyp from one of those patients. Two other family members, one with a rectal carcinoma aged 55, the other with two separate benign lesions under the age of 45, were both wild-type for the TP53 mutation.