A compound attribute that is the ratio of amount of GRB2-related adapter protein 2 (human) in blood to amount of pyridoxal phosphate homeostasis protein (human) in blood. The trait is GRAP2/PLPBP protein level ratio in blood (OBA_2053442, an Ontology of Biological Attributes term). Also known as: the ratio of amount of GRB2-related adapter protein 2 (human) in blood to amount of pyridoxal phosphate homeostasis protein (human) in blood.