Clinical Neuroscience

[Apolipoprotein E4 as a genetic risk factor in Alzheimer's Disease]

KÁLMÁN János1, JANKA Zoltán1

SEPTEMBER 20, 1996

Clinical Neuroscience - 1996;49(09-10)

[Apolipoprotein E (apoE) is a glycoprotein participating in the lipid transport and metabolism and in the neuronal regeneration processes. The gene of apo (APOE) is localized on the long arm of chromosome 19. The genetic polymorphism of APOE is manifested in three common alleles. The frequencies of these alleles, APOE2, APOE3, APOE4 are different in various human populations depending on their geographical origin. The APOE alleles have been considered to be responsible for the inter-individual variations of the serum cholesterol level. Besides its function in lipid transport, there are other relatively unknown but proven functions of apoE in the development of the nervous system and in peripheral nerve regeneration after injury. ApoE is considered as an important etiophathogenetic factor of atherosclerosis, familial hypercholesterolaemia and hyperlipoproteinaemia type III. The results of biochemical, molecular biological, population genetic and neuropathological examinations of the last three years have provided evidence that APOE4 alleles could be important risk factors of Alzheimer's dementia (AD). Recent findings regarding the relationship of apoE and AD are reviewed by the authors in connection with other aetiopathogenetic factors such as development of senile plaques, mutations of amyloid precursor protein gene, familial and sporadic forms of AD. These factors are discussed in relation to the therapeutic implications and dilemmas of genetic testing of APOE in AD.]

AFFILIATIONS

  1. Szent-Györgyi Albert Orvostudományi Egyetem Ideg- és Elmegyógyászati Klinika, Szeged

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Clinical Neuroscience

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