A compound attribute that is the ratio of amount of carbonic anhydrase 13 (human) in blood to amount of STAM-binding protein (human) in blood. The trait is Ontology of Biological Attributes entry OBA_2055724 (CA13/STAMBP protein level ratio in blood). Also known as: the ratio of amount of carbonic anhydrase 13 (human) in blood to amount of STAM-binding protein (human) in blood.