Regional brain atrophy in cognitively intact adults with a single APOE epsilon4 allele.
OBJECTIVE
To determine whether cognitively intact adults with the APOE epsilon3/epsilon4 genotype show reduced gray matter density on voxel-based morphometry (VBM) vs those homozygous for the epsilon3 allele.


METHODS
Participants were healthy, cognitively intact, right-handed adults, age 19 to 80, who completed genotyping, neuropsychological testing, and MRI. Forty-nine participants had the epsilon3/epsilon3 genotype and 27 had the epsilon3/epsilon4 genotype. Gray matter data were analyzed using the general linear model as implemented in the Statistical Parametric Mapping package, adjusting for age and sex.


RESULTS
The epsilon3/epsilon4 participants showed lower gray matter density than the epsilon3/epsilon3 participants in right medial temporal and bilateral frontotemporal regions as well as other areas. There were no regions in which epsilon3/epsilon4 participants showed higher gray matter density than epsilon3/epsilon3 participants.


CONCLUSIONS
Regionally reduced gray matter density is detectable in cognitively intact adults with a single copy of the APOE epsilon4 allele.
Wishart
H A
HA
Department of Psychiatry, Dartmouth Medical School/DHMC, Lebanon, NH 03756-0001, USA.
Saykin
A J
AJ
McAllister
T W
TW
Rabin
L A
LA
McDonald
B C
BC
Flashman
L A
LA
Roth
R M
RM
Mamourian
A C
AC
Tsongalis
G J
GJ
Rhodes
C H
CH
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics*; D001284:Atrophy / Q000175:diagnosis / Q000235:genetics; D001921:Brain / Q000378:metabolism* / Q000473:pathology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000235:genetics; D004252:DNA Mutational Analysis; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009474:Neurons / Q000473:pathology*
D053327:Apolipoprotein E4; D001057:Apolipoproteins E