COWDENS-DISEASE WITH A DEFINED GENETIC ALTERATION-CHROMOSOMAL DUPLICATION AT 15Q11-Q13

Cowden's disease, multiple hamartoma syndrome, is a dominantly inherit ed disorder characterized by multiple hamartomas of ectodermal, endode rmal, and mesodermal origin and also by a high incidence of malignant tumors. Despite many efforts to identify the genetic alterations respo nsible for the syndrome, the molecular mechanism remains unclear. We r eport 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.