Phenotypic findings of Cowden syndrome and Bannayan-Zonana syndrome in a family associated with a single germline mutation in PTEN

Cowden syndrome (CS) and Bannayan-Zonana syndrome (BZS) are two hamartoma s yndromes with distinct phenotypic features. Although partial clinical overl ap exists between CS and BZS, they are considered to be separate entities. PTEN has been identified as the susceptibility gene for both disorders, sug gesting allelism. We have identified a germline mutation, R335X, in PTEN in a family consisting of two female members with the phenotypic findings of CS and two male members with the phenotypic findings of BZS. To our knowled ge, this is the first report that shows the presence of separate subjects w ith CS and with BZS in a single family associated with a single germline PT EN mutation.