CA13/COMT protein level ratio in blood (OBA_2055715) can be described as follows. A compound attribute that is the ratio of amount of carbonic anhydrase 13 (human) in blood to amount of catechol O-methyltransferase (human) in blood. Also known as: the ratio of amount of carbonic anhydrase 13 (human) in blood to amount of catechol O-methyltransferase (human) in blood.