Elsevier

Neuroscience Letters

Volume 236, Issue 1, 24 October 1997, Pages 21-24
Neuroscience Letters

Reduced size of right hippocampus in 39- to 80-year-old normal subjects carrying the apolipoprotein E ϵ4 allele

https://doi.org/10.1016/S0304-3940(97)00743-XGet rights and content

Abstract

Hippocampal size on magnetic resonance imaging was compared between normal subjects with the apolipoprotein E (apo E) ϵ4 allele (ϵ4/4, ϵ4/3, and ϵ4/2) and those without the ϵ4 allele (ϵ3/3, ϵ3/2, and ϵ2/2) in the age range of 39–80 years. The Mini-Mental State Examination (MMSE) scores did not differ between the two groups. The right hippocampal area and its ratio to hemisphere area and intracranial cavity area were significantly smaller in ϵ4 carriers than non-carriers, whereas hemisphere area did not differ between the two groups. These results suggest that as early as their forties, apo E ϵ4 allele carriers have a markedly smaller right hippocampus with no apparent cognitive impairment, which may have some significance in the high prevalence of the ϵ4 allele in Alzheimer's disease as well as other conditions that cause dementia.

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Acknowledgements

We thank Professor Akira Ogawa and Dr. Naohiko Kubo of the Department of Neurosurgery for their cooperation with the Clinic for the Detection of Asymptomatic Brain Disease and to Ms. Shiho Hinata for her secretarial assistance. This study was supported in part by the Ministry of Health and Welfare and the Ministry of Education, Science and Culture, Japan.

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