Ontology of Biological Attributes identifier OBA_2053639 (AGRN/BTN2A1 protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of agrin (human) in blood to amount of butyrophilin subfamily 2 member A1 (human) in blood. Also known as: the ratio of amount of agrin (human) in blood to amount of butyrophilin subfamily 2 member A1 (human) in blood.