Phenotype variability in tumor disorders of the skin appendages associated with mutations in the <i>CYLD</i> gene

Mutations in the tumor suppressor gene CYLD underlie phenotypically heterogeneous hereditary tumor disorders of the skin appendages. These diseases are inherited autosomal dominantly and include Brooke-Spiegler syndrome (BSS; OMIM 605041), familial cylindromatosis (FC; OMIM 132700) and multiple familial trichoepithelioma (MFT; OMIM 601606). Clinically, cylindromas, trichoepitheliomas and spiradenomas can be found in affected individuals. We sought to elucidate the molecular genetic basis in individuals with newly diagnosed cylindromas, trichoepitheliomas and/or spiradenomas. Mutation analysis using polymerase chain reaction (PCR)-based techniques was performed in seven German patients and one Turkish patient. We detected two missense, two nonsense, two deletions and two duplication mutations in the CYLD gene, of which seven have not yet been reported. No genotype-phenotype correlation was detected amongst the patients. Our data provide additional information on the clinical and molecular genetic heterogeneity of disorders associated with CYLD mutations.