Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND: Genome-wide association studies have established 11 genes for late-onset Alzheimer's disease (AD). We investigated whether these genes jointly affect cognition in a nondemented population and improve prediction of AD. METHODS: In 5171 nondemented people (age 45-99 years) from the population-based Rotterdam Study, we genotyped APOE-ε4 and single nucleotide polymorphisms from the genes CLU, PICALM, BIN1, CR1, ABCA7, MS4A6A, MS4A4E, CD2AP, EPHA1, and CD33. We constructed a genetic risk score by adding the risk alleles per individual weighted by the reported effect sizes. All people underwent cognitive testing. With linear regression we investigated the relationship between the genetic risk score and cognition, with and without APOE. In a subcohort, with more than 10 years of follow-up, we assessed whether the risk score predicted AD. RESULTS: The genetic risk score was primarily associated with memory (standardized difference [95% confidence interval] per SD increase in genetic risk score: -.05[-.07; -.02], p = 1.5 * 10(-4)). This association attenuated when APOE was excluded from the genetic risk score (-.03[-.05; .00], p = .047) and would not survive a multiple-testing correction. Similarly, we found that although the genetic risk score without APOE was associated with the development of AD (p = .010), it only marginally improved prediction of AD beyond age, sex, APOE (area under the curve: .8159 vs. .8148). CONCLUSIONS: In nondemented people, there is only a marginal joint effect of AD genes on memory independent from APOE. Moreover, although associated with AD, these genes jointly hardly improve prediction of AD.

Original publication

DOI

10.1016/j.biopsych.2012.04.009

Type

Journal article

Journal

Biological psychiatry

Publication Date

03/2013

Volume

73

Pages

429 - 434

Addresses

Department of Epidemiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.

Keywords

Humans, Alzheimer Disease, Genetic Predisposition to Disease, Apolipoproteins E, Cognition, Cognition Disorders, Neuropsychological Tests, Genotype, Polymorphism, Single Nucleotide, Aged, Aged, 80 and over, Middle Aged, Female, Male, Genome-Wide Association Study