Cowden's disease with a defined genetic alteration--chromosomal duplication at 15q11-q13

Cowden's disease, multiple hamartoma syndrome, is a dominantly inherited disorder characterized by multiple hamartomas of ectodermal, endodermal, and mesodermal origin and also by a high incidence of malignant tumors. Despite many efforts to identify the genetic alterations responsible for the syndrome, the molecular mechanism remains unclear. We report a case of Cowden's disease in which karyotype analysis revealed a small duplication (about 1 Mb) at 15q11-q13. This part of the genome is a region that is deleted in the Prader-Willi/Angelman syndrome and is a "hot spot" of chromosomal duplication.