ABSTRACT
BACKGROUND: Frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17) owing to the tau intron 10 + 16 mutation usually occurs with a prototypical frontotemporal dementia phenotype with prominent disinhibition and affective disturbances. OBJECTIVE: To report a new FTDP-17 pedigree with the tau intron 10 + 16 mutation demonstrating a clinical phenotype suggestive of Alzheimer disease. DESIGN: Case reports. SETTING: Regional neuroscience centers in northwest England. Patients We examined 4 members of a kindred in which 8 individuals were affected in 3 generations. RESULTS: All 4 patients reported memory difficulty. Marked anomia was also present, but behavioral disturbances were conspicuously absent in the early stages of disease. All patients had an initial clinical diagnosis of Alzheimer disease. No mutations were found in the presenilin or amyloid precursor protein genes. Pathologic examination of the proband showed features typical of FTDP-17, and tau gene analysis showed the intron 10 + 16 mutation. CONCLUSIONS: This pedigree illustrates the phenotypic variability of tau intron 10 + 16 mutations. In pedigrees with a clinical diagnosis of Alzheimer disease but without presenilin or amyloid precursor protein gene mutations, tau gene mutations may be found.
Subject(s)
Alzheimer Disease/psychology , Dementia/genetics , Dementia/psychology , Introns/genetics , tau Proteins/genetics , Adult , Atrophy , Cerebral Cortex/pathology , Disease Progression , Family , Fatal Outcome , Female , Hippocampus/pathology , Humans , Male , Middle Aged , Mutation/genetics , Mutation/physiology , Neuropsychological Tests , PedigreeABSTRACT
Both Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share a common neuropathological marker, the presence of Lewy bodies in brain stem and basal forebrain nuclei. DLB, in addition, is associated with Lewy bodies in the neocortex, and, in it's more common form, with Alzheimer-type pathological markers, particularly amyloid plaques. Published neuropsychological studies have focused on the differential profiles of DLB and Alzheimer's disease (AD). However, it is presently unclear whether DLB should be classified as a variant of AD or PD. In the present study we compare a healthy age-matched control group with three groups of patients, one with DLB, and two with PD. One of the PD groups was early in the course (PD-E) and the second, more advanced group (PD-A), was matched on severity of cognitive impairment with the DLB group. The results show that DLB was associated with a different pattern of neuropsychological impairment than the PD-A group, particularly in tests believed to be mediated by prefrontal cortical regions.
