The angiopoietins are protein growth factors that promote angiogenesis, the formation of blood vessels from pre-existing blood vessels. There are now four identified angiopoietins: Ang1, Ang2, Ang3, Ang4. In addition, there are a number of proteins that are closely related to angiopoietins (ANGPTL2, ANGPTL3, ANGPTL4, ANGPTL5, ANGPTL6, ANGPTL7). Angiopoietin-like 5 (ANGPTL5) is mainly expressed in adult heart. Like other members of the angiopoietin family, ANGPTL5-deduced protein also has an N-terminal cleavable signal peptide, a predicted coiled-coil domain, and a fibrinogen-like domain. ANGPTL5 are regulators of lipoprotein metabolism in humans. ANGPTL5 plays nonredundant roles in TG metabolism, and multiple alleles at these loci cumulatively contribute to variability in plasma TG levels in humans.