title: ApoE genotype and abnormal auditory cortical potentials in healthy older females.
abstract: Apolipoprotein E (ApoE) status and gender are risk factors for the development of Alzheimer's disease. Alzheimer's disease is more prevalent in female relative to male carriers of the ApoE epsilon 4 gene. We examined cortical sensory (P50, N100) and cognitive (P300) potentials in an auditory target detection task in females as a function of ApoE genotype (ApoE epsilon 4 carriers, ApoE epsilon 4 non-carriers) to define the incidence of abnormalities prior to the clinical expression of cognitive impairments. Both neuropsychological test scores and sensory cortical potentials did not differ between the two ApoE groups. In contrast, cognitive P300 potentials were significantly decreased in amplitude and delayed in latency for ApoE epsilon 4 carriers compared to non-carriers. Four out of the 10 ApoE epsilon 4 carriers had abnormally (>2S.D.) delayed P300 latency compared to one out of 20 non-carriers. Abnormal cognitive processes reflected by P300 latency delays are expressed at significantly higher incidence in normal older females who are carriers of the epsilon 4 allele than in non-carriers of this allele.
authors.affiliation: Department of Neurology and Institute for Brain Aging and Dementia, University of California, Irvine, CA 92627, USA.
authors.forename: Rie
authors.initials: R
authors.lastname: Irimajiri
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Golob
authors.forename: Arnold
authors.initials: A
authors.lastname: Starr
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000235:genetics; D053327:Apolipoprotein E4 / Q000235:genetics*; D001303:Auditory Cortex / Q000502:physiology*; D001307:Auditory Perception / Q000235:genetics*; D001308:Auditory Perceptual Disorders / Q000235:genetics*; D005071:Evoked Potentials / Q000235:genetics; D005072:Evoked Potentials, Auditory / Q000235:genetics / Q000502:physiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D009483:Neuropsychological Tests
chemical_list: D053327:Apolipoprotein E4