A compound attribute that is the ratio of amount of complement decay-accelerating factor (human) in blood to amount of prostaglandin-H2 D-isomerase (human) in blood. The trait is CD55/PTGDS protein level ratio in blood (OBA_2054161, an Ontology of Biological Attributes identifier). Also known as: the ratio of amount of complement decay-accelerating factor (human) in blood to amount of prostaglandin-H2 D-isomerase (human) in blood.