Other primary forms include abetalipoproteinemia, characterized by a virtual absence of apoB-containing lipoproteins, the Anderson disease, or chylomicron retention syndrome, and combined familial hypolipidemia, which is due to a mutation of the gene for the angiopoietin-like 3 (ANGPTL3) protein. This evidence concerns the gene ANGPTL3 and chylomicron retention disease.