apolipoprotein E

(redirected from APOE gene)

ap·o·lip·o·pro·tein E

an apolipoprotein found in several plasma lipoprotein particles including chylomicrons, VLDL, and HDL. Three major isoforms are encoded by three common alleles at the Apo E locus: E2, E2, and E4. The E2 allele is associated with lower total plasma cholesterol and LDL cholesterol than is E3, whereas E4 is associated with higher LDL and total cholesterol than E3.

apolipoprotein E

a protein component of lipoprotein complexes found in very-low-density lipoprotein (VLDL), high-density lipoprotein, chylomicrons, and chylomicron remnants. It facilitates hepatic uptake of chylomicron and VLDL remnants and is elevated in patients with type III hyperlipoproteinemia. One form of apolipoprotein E has been linked to Alzheimer's disease.


A gene on chromosome 19q13.2 that encodes apolipoprotein E, the main apoprotein of chylomicrons, which binds to a specific receptor on liver cells and peripheral cells. ApoE mediates binding, internalisation and catabolism of lipoprotein particles and serves as a ligand for the LDL (apo B/E) receptor.

Molecular pathology
APOE mutations cause hyperlipoproteinaemia type III (familial dysbetalipoproteinaemia), which is characterised by increased plasma cholesterol and triglycerides due to impaired chylomicron and VLDL remnant clearance.

apolipoprotein E

A 34-kD cholesterol-binding glycoprotein, which comprises 15% of VLDL; apoE maps to chromosome 19, is secreted by macrophages that mediate the uptake of lipoproteins–VLDL, HDL, LDL and cholesterol esters into cells via distinct binding domains for each receptor; apo-E has a central role in the metabolism of TG-rich lipoproteins, and mediates the uptake of chylomicrons and VLDL by the liver
References in periodicals archive ?
ApoE gene amplification and typing were performed as described by Saunders et al.
Depending on which apoE gene a person has, the apoE protein will differ in structure and function.
The sequences of oligonucleotides oligo 3 and oligo 4 were identical to the one around codon 112 of the APOE gene; oligonucleotides oligo 3b and oligo 2 are the same as the sequence around codon 158 of the APOE gene.
Further analysis of the studies revealed that patients administered Axona who lacked the epsilon 4 variant of the APOE gene (E4(-)), demonstrated significant improvement from baseline values in the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-Cog) and improvement compared to placebo.
Hegele's finding of unique disease-causing mutations in the APOE gene during routine genotyping for Alzheimer disease highlights the continuing need for broad patient-oriented clinical observation and intervention as genetic discoveries and tests move from the research laboratory into clinical use.
Our data suggest that women who inherit distinct alleles of the APOE gene may require individualized ERT or combination therapy.
The ApoE gene has been linked to optic nerve and visual field damage in glaucoma patients.
According to the researchers, the REVEAL study (Risk Evaluation and Education for Alzheimer's disease) is the first randomized trial to examine the impact of providing risk assessment, including APOE gene marker disclosure, for Alzheimer's disease.
In familial defective apolipoprotein B-100, the clearance of LDL particles from the circulation is impaired because of reduced affinity of the apolipoprotein (apo) B component of LDL for the LDL receptor as a result of a G-to-A mutation at nucleotide 10708 in exon 26 of the apoE gene, which causes substitution of [Arg.
At the APOE gene locus, three common alleles exist, designated [euro]2, [euro]3, and [euro]4 (3-5).
and his colleagues at Duke, found that the presence of the ApoE4 form of the ApoE gene significantly increases the probability that a patient's dementia is caused by Alzheimer's disease.