Apolipoprotein E4

In medicine, apolipoprotein E4 (apolipoprotein ε4) is an apolipoprotein which is "a major and the second most common isoform of apolipoprotein E. In humans, Apo E4 differs from apolipoprotein E3 at only one residue 112 (cysteine is replaced by arginine), and exhibits a lower resistance to denaturation and greater propensity to form folded intermediates. Apo E4 is a risk factor for Alzheimer disease and cardiovascular diseases.