Parental origin of chromosome 9q22.3-q31 lost in basal cell carcinomas from basal cell nevus syndrome patients.

The basal cell nevus syndrome is an autosomal dominant disease, one of the most prominent phenotypic features of which is a large number of cutaneous basal cell carcinomas. The gene whose mutation underlies this disease has been mapped to chromosome 9q22.3-q31, and basal cell carcinomas frequently have allelic losses including this site. We report here that the chromosome 9q22.3-q31 lost in 24 basal cell carcinomas from basal cell nevus syndrome patients was the one predicted by linkage to contain the wild-type gene. Hence these data are compatible with the exception that the product of the basal cell nevus syndrome gene acts as a tumor suppressor.