It is defined as “a benign uni- or multicystic, intraosseous tumor of odontogenic origin, with a characteristic lining of parakeratinized stratified squamous epithelium and potential for aggressive, infiltrative behaviour". The genetic basis for this was a tumor suppressor gene, PTCH (“patched”), which is involved in both sporadic KCOTs and NBCCS occurring on chromosome 9q22.3-q31, and if regular functioning of PTCH [5] vanishes, the proliferation-stimulating effects of SMO (smoothened) predominate. The gene discussed is PTCH1; the disease is neoplasm.