AHCY/GRAP2 protein level ratio in blood (Ontology of Biological Attributes term OBA_2053650) can be described as follows. A compound attribute that is the ratio of amount of adenosylhomocysteinase (human) in blood to amount of GRB2-related adapter protein 2 (human) in blood. Also known as: the ratio of amount of adenosylhomocysteinase (human) in blood to amount of GRB2-related adapter protein 2 (human) in blood.