1. Department of Dermatology, University of California, San Francisco, California, U.S.A.
2. ^*Departments of Developmental Biology and Genetics, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California, U.S.A.

Correspondence: Dr Ervin H. Epstein, Jr., Bldg 100 Room 269, San Francisco General Hospital, 1001 Potrero Avenue, San Francisco, CA 94110

Received 1 November 1997; Revised 30 January 1998; Accepted 19 February 1998.

Abstract

Mutations in PATCHED (PTC), the human homolog of the Drosophila patched gene, have been identified in most exons of the gene in patients with the basal cell nevus syndrome and in sporadic basal cell carcinomas. We have screened the 23 PTC exons for mutations using single strand conformation polymorphism analysis of DNA from 86 basal cell nevus syndrome probands, 26 sporadic basal cell carcinomas, and seven basal cell nevus syndrome-associated basal cell carcinomas. This screen identified mutations located in eight exons in 13 of the basal cell nevus syndrome patients and in three of the tumors. The most common mutations were frameshifts resulting in premature chain termination. These results provide further evidence for the crucial role of PTC as a tumor suppressor in human keratinocytes.