Ontology of Biological Attributes identifier OBA_2055176 (APOM/MCAM protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of apolipoprotein M (human) in blood to amount of cell surface glycoprotein MUC18 (human) in blood. Also known as: the ratio of amount of apolipoprotein M (human) in blood to amount of cell surface glycoprotein MUC18 (human) in blood.