Apolipoprotein E polymorphism: automated determination of apolipoprotein E2, E3, and E4 isoforms.

Apolipoprotein E (apo E) plays an essential role in lipoprotein metabolism, where it is involved in the clearance of chylomicrons and very low density lipoproteins. Apart from some rare variants, apo E exists in three common isoforms (E2, E3, and E4). The different isoforms have not only been associated with different plasma lipid levels but have also been correlated with certain pathological conditions, such as lipid disorders (dysbetalipoproteinemia, hypercholesterolemia), cardiovascular diseases, and Alzheimer's disease. Here we describe a rapid, automated test for the determination of the most frequent polymorphisms (E2, E3, and E4). This polymerase chain reaction-based test allows the reliable discrimination of all six genotypes. The assay has been developed especially for the nonspecialized routine clinical laboratory by employing an analyzer and chemistry often present in this type of laboratory. Because of its low costs and easy handling, the assay can be performed on a daily basis.