Apolipoprotein E and intellectual achievement.
OBJECTIVE
To determine whether apolipoprotein E (apo E) genotype influences intellectual achievement in cognitively normal individuals.


METHODS
Between 1994 and 1999 we performed apo E testing on 1,000 self-described cognitively normal residents of Maricopa County and detailed neuropsychological testing on a subset of 250.


METHODS
Tertiary care academic medical center.


METHODS
Cognitively normal adults genotyped for apo E.


METHODS
Measures of intellectual background included years of education and a demographically based estimate of intellectual capacity (demographic intellectual quotient (DIQ)). Measures of intellectual achievement, which included Wechsler Adult Intelligence Scale revised (WAIS-R), information (WAISI), and vocabulary (WAISV) scores, occupational intellectual requirements (OIR), and census-derived estimates of household income, were compared between apo E genetic subgroups while adjusting for intellectual background and demographic variables.


RESULTS
WAISI, WAISV, OIR, and income correlated with age, sex, education, and DIQ, but after controlling for these variables there were no clinically significant differences between apo E-e4 homozygotes and noncarriers on any measure.


CONCLUSIONS
No clinically significant differences between genotypes were observed for the effects of education and DIQ on WAISI, WAISV, OIR, or income, although a larger sample size would be required to exclude smaller, clinically insignificant differences.
Caselli
Richard J
RJ
Department of Neurology, Mayo Clinic, Scottsdale, Arizona 85259, USA.
Hentz
Joseph G
JG
Osborne
David
D
Graff-Radford
Neill R
NR
Barbieri
Carolyn J
CJ
Alexander
Gene E
GE
Hall
Geri R
GR
Reiman
Eric M
EM
Hardy
John
J
Saunders
Ann M
AM
D001057:Apolipoproteins E / Q000235:genetics*; D001130:Arizona; D004522:Educational Status; D005260:Female; D006720:Homozygote; D006801:Humans; D007182:Income; D007360:Intelligence / Q000235:genetics*; D007361:Intelligence Tests; D008297:Male; D009790:Occupations
D001057:Apolipoproteins E