Spastic paraparesis and atypical dementia caused by PSEN1 mutation (P264L), responsible for Alzheimer's disease

2 to 15 years), in contrast to this family.Our results strongly suggest that the association of dementia and spastic paraparesis is not restricted to specific PSEN1 mutations, but may also represent variable phenotypic expression of more common mutations usually causing typical Alzheimer's disease.It is interesting that the P264L mutation can result in dementia that is not typical of Alzheimer's disease.. . . . . . .