The demonstration that mutations in the Patched (PTCH) gene cause nevoid basal cell carcinoma syndrome (NBCCS) has led to the identification of the exact molecular lesion in a percentage of individuals with the syndrome.
INTRODUCTION AND DISCUSSION: Molecular genetic investigations relating to thyroid cancer have started to gain clinical importance, with discovery of the tumor-specific oncogenes PTC 1-3 in papillary thyroid cancer and the syndrome-specific mutations of the RET protooncogene in MEN-2a, MEN-2b and familial MTC patients.
PTCH gene mutation has been shown to be an important step in the pathogenesis of the OKC and was thought to have a role in the development of the sporadic as well as the syndrome-related OKCs.
Eleven new germline alterations of the PTCH gene were characterised in 12 out of 17 patients harbouring the full complement of criteria for the syndrome (70%).
We describe a Gorlin syndrome case with typical features of the syndrome and no mutations in PTCH1, but with a large deletion of the 9q22 region that has rarely been described.
The syndrome is primarily caused by mutations in the Patched 1 (PTCH1) gene, although rare mutations of Patched 2 (PTCH2) or Suppressor of Fused (SUFU) genes have also been found.