A novel Italian presenilin 2 gene mutation with prevalent behavioral phenotype.

Presenilin mutations are the main cause of familial Alzheimer's disease. So far, more than 160 mutations in the Presenilin 1 gene (PSEN1) and approximately 10 mutations in the homologous Presenilin 2 gene (PSEN2) have been identified. Some PSEN1 mutations are associated with a phenotype fulfilling the clinical criteria of frontotemporal dementia. In PSEN2, T122P and M239V mutations presented with severe behavioral disturbances. We describe an Italian patient with a novel PSEN2 mutation (Y231C) who showed behavioral abnormalities and language impairment as presenting symptoms, with later involvement of other cognitive abilities, particularly of posterior functions.