Pick bodies in a family with presenilin-1 Alzheimer's disease.

Presenilin-1 (PS-1) mutations can cause Pick's disease without evidence of Alzheimer's disease (AD). We describe a family with a PS-1 M146L mutation and both Pick bodies and AD. Sarkosyl-insoluble hyperphosphorylated tau showed three bands consistent with AD, although dephosphorylation showed primarily three-repeat isoforms. M146L mutant PS-1 may predispose to both Pick's disease and AD by affecting multiple intracellular pathways involving tau phosphorylation and amyloid metabolism.