Total and regional gray matter volume is not related to APOE*E4 status in a community sample of middle-aged individuals.

BACKGROUND The APOE*E4 allele has been associated with greater gray matter atrophy and with Alzheimer's disease. The aim of this study was to investigate whether the relationship between cerebral gray matter atrophy and APOE*E4 genotype was also present in a community-dwelling, nondemented 60- to 64-year-old cohort. METHODS Hippocampal and amygdalar volumes were manually traced and analyzed on 331 cranial T1-weighted magnetic resonance imaging (MRI) scans to detect differences associated with APOE*E4 genotype. Voxel-based morphometric (VBM) analyses were applied to detect regional gray matter volume differences. RESULTS No total, hippocampal, or amygdalar gray matter volume difference was detected between APOE*E4 carriers and noncarriers. CONCLUSIONS In nondemented 60- to 64-year-olds, there was no association between APOE genotype and gray matter volume using both region-of-interest analysis and VBM.