A compound attribute that is the ratio of amount of nectin-4 (human) in blood to amount of serine protease inhibitor Kazal-type 5 (human) in blood. The trait is NECTIN4/SPINK5 protein level ratio in blood (OBA_2055122, an Ontology of Biological Attributes term). Also known as: the ratio of amount of nectin-4 (human) in blood to amount of serine protease inhibitor Kazal-type 5 (human) in blood.