Combined gene effects on hippocampal mnemonic processing : a large-scale imaging-genetics study of APOE, BDNF, KIBRA, and CLSTN2

• Twin studies have revealed that memory and relatedbrain functions are highly heritable traits, but putative candidate geneshave shown small and inconsistent effects -referred to as "the missing heritability". Little is known about the combined effect of several genes onbrain function: whether the presence of one "risk" variant hides the effect ofanother, interacts with it, or increases the risk in an additive -or even multiplicative -way. In a large fMRI sample we explored the combined effect ofpolymorphisms with documented impact on brain activation in the medialtemporal lobe (MTL) during episodic memory encoding or retrieval. Analyses of the effects of individual genes revealed decreased MTL activationfor ApoE £4 and BDNF Met alíeles during encoding, and for Kibra CCand the CLSTN2 T alíele during retrieval. Analyses of combined effectsrevealed that, during encoding, carriers of both the ApoE £4 and the BDNFMet alíele had lowest MTL activation, whereas non

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Fysiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Physiology (hsv//eng)

Publication and Content Type

vet (subject category)

art (subject category)