A compound attribute that is the ratio of amount of protocadherin-17 (human) in blood to amount of thrombomodulin (human) in blood. The trait is PCDH17/THBD protein level ratio in blood (Ontology of Biological Attributes identifier OBA_2054038). Also known as: the ratio of amount of protocadherin-17 (human) in blood to amount of thrombomodulin (human) in blood.