A compound attribute that is the ratio of amount of proepiregulin (human) in blood to amount of proheparin-binding EGF-like growth factor (human) in blood. The trait is EREG/HBEGF protein level ratio in blood (Ontology of Biological Attributes id OBA_2054746). Also known as: the ratio of amount of proepiregulin (human) in blood to amount of proheparin-binding EGF-like growth factor (human) in blood.