A presenilin 1 R278I mutation presenting with language impairment

Presenilin (PSEN)1 mutations are responsible for many cases of autosomal dominant Alzheimer disease ( AD), although the clinical spectrum has not been fully defined. The authors describe two members of a kindred with a novel PSEN1 mutation (R278I) presenting with language impairment and relative preservation of memory. Screening for PSEN1 mutations may be appropriate in cases of familial dementia even where the clinical phenotype is not typical of AD.