We demonstrate the efficiency and reproducibility of the method in which we screen a DNA fragment encompassing exon 5 of the PTCH gene (in which mutations cause Gorlin Syndrome) in a panel of 22 patients.
Unresolved complexities of the pathway impede understanding of mechanisms through which PTCH alterations lead to variable phenotype expression in Gorlin syndrome patients, while the role of chromosomal instability is not yet clear.
Germline mutations of the human patched gene, PTCH, are responsible for the nevoid basal cell carcinoma (NBCC) syndrome or Gorlin's syndrome, characterized by multiple skin cancers, internal cancers and severe developmental abnormalities.
Loss of heterozygosity for the PTCH region was found several years ago in the epithelial lining of odontogenic keratocysts, the cyst type with highly increased incidence in nevoid basal cell carcinoma syndrome.
The nevoid basal cell carcinoma syndrome (NBCCS), which is caused by mutations of PTCH gene on chromosome 9q22, accounts for about 2% of all medulloblastomas.
With identification of the Hedgehog receptor PTCH1 as a tumour suppressor gene that underlies the human nevoid basal cell carcinoma syndrome (NBCCS), the Hedgehog signalling pathway was firmly linked to cancer.
Genetic analysis of the PTCH gene is essential for the early, definitive diagnosis of NBCCS, especially before the expression of clinical manifestations is complete.
Individuals with germline mutations of the SHH receptor gene PTCH are at high risk of developmental anomalies and of basal-cell carcinomas, medulloblastomas and other cancers (a pattern consistent with nevoid basal-cell carcinoma syndrome, NBCCS).
The finding of mutations in the PTCH gene in both Gorlin's syndrome and sporadic basal cell carcinomas has significantly advanced our understanding of the molecular defects that lead to the formation of these tumours.
Ptc+/- mouse is a useful model of BCNS from the standpoint of occurrence of jaw cysts, and downregulation of ptc protein in cyst lining epithelium caused by gene targeting would be associated with formation of jaw cysts in ptc+/- mice.
The phenotype of Gorlin-Goltz syndrome or basal cell nevus syndrome (BCNS, #109400, OMIM), a Mendelian trait due to PTCH mutations has been reported in a few cases of interstitial deletion of chromosome 9q.
We report the clinical manifestations of a Taiwanese family with NBCCS and mutation analysis of the PTCH gene from peripheral blood, OKC tissues, and cyst content.
Mice in which one copy of Ptch1 is inactivated show increased susceptibility to spontaneous tumor development and hypersensitivity to radiation-induced tumorigenesis, providing an ideal in vivo model to study the typical pathologies associated with basal cell nevus syndrome.