THE GENE FOR THE NEVOID BASAL-CELL CARCINOMA SYNDROME ACTS AS A TUMOR-SUPPRESSOR GENE IN MEDULLOBLASTOMA

Individuals with naevoid basal cell carcinoma (Gorlin) syndrome are at increased risk of developing medulloblastoma in childhood. We have sh own that approximately 5% of patients with Gorlin syndrome will develo p this complication in the first few years of life, and in addition 10 % of patients with medulloblastoma diagnosed at age 2 years or under h ave Gorlin syndrome. One out of three medulloblastomas occurring in pa tients with Gorlin syndrome was shown to have lost the wild-type allel e on 9q, indicating that the Gorlin locus probably acts as a tumour su ppressor in the development of this tumour, We have also confirmed thi s role in a basal cell carcinoma (BCC) from the same individual, Infor mation from these families would suggest that Gorlin syndrome is more common than previously recognized and may not always be diagnosed on c linical grounds alone even in middle life.