Alleles of apolipoprotein

There are 3 isoforms of apolipoprotein (ApoE) designated ε2,ε3 and ε4. ApoE is a constituent of a subclass of high-density lipoproteins involved in cholesterol transport activity. The presence of the ε4 isoform of ApoE4 has been shown to increase the risk of developing Alzheimer’s disease (AD) and to decrease the age of onset for AD and is the major genetic risk factor for the late-onset form of the disease. ApoE4 intensifies all the biological hallmarks of AD including amyloid deposition, neurofibrillary tangle formation, increase neuronal cell death, oxidative stress, synaptic plasicity and cholinergic signalling. In contrast, other ApoE isoforms are protective.

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References

J Cell Mol Med 2001;5:254–266.

Physiological Reviews 2001;81:741–766.