A compound attribute that is the ratio of amount of pyridoxal phosphate homeostasis protein (human) in blood to amount of sorting nexin-9 (human) in blood. The trait is PLPBP/SNX9 protein level ratio in blood (OBA_2053519). Also known as: the ratio of amount of pyridoxal phosphate homeostasis protein (human) in blood to amount of sorting nexin-9 (human) in blood.