A compound attribute that is the ratio of amount of OX-2 membrane glycoprotein (human) in blood to amount of contactin-associated protein-like 2 (human) in blood. The trait is Ontology of Biological Attributes term OBA_2055285 (CD200/CNTNAP2 protein level ratio in blood). Also known as: the ratio of amount of OX-2 membrane glycoprotein (human) in blood to amount of contactin-associated protein-like 2 (human) in blood.