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Meta-analysis of cognitive ability differences by apolipoprotein e genotype in young humans
Gali H Weissberger1, Daniel A Nation2, Caroline P Nguyen1
1Department of Family Medicine, USC Keck School of Medicine, 1000 S. Fremont Avenue, Unit 22, HSA Building A-6, 4thFloor, Room 6437A, Alhambra, CA, 91803, USA.
Abstract:
The apolipoprotein (APOE) ε4 allele has been proposed as an example of an antagonistic pleiotropy gene, conferring a beneficial effect on cognition in early life and a detrimental impact on cognition during later years. However, findings on the cognitive associations of the ε4 allele in younger persons are mixed. This PRISMA conforming study aimed to investigate APOE genotype (e4/non-e4) associations across seven cognitive domains (intelligence/achievement, attention/working memory, executive functioning, memory, language, processing speed and visuospatial abilities) in younger humans using a meta-analytic approach. Of 689 records reviewed, 29 studies (34 data-points) were selected for the quantitative synthesis. Participants' ages ranged from 2-40. Results showed that young ε4 carriers did not statistically differ from non-ε4 carriers across any cognitive domains. Overall, findings do not provide compelling support for an antagonistic pleiotropic effect of the ε4 allele across the lifespan.
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