A compound attribute that is the ratio of amount of neural proliferation differentiation and control protein 1 (human) in blood to amount of prostaglandin-H2 D-isomerase (human) in blood. The trait is NPDC1/PTGDS protein level ratio in blood (OBA_2055137). Also known as: the ratio of amount of neural proliferation differentiation and control protein 1 (human) in blood to amount of prostaglandin-H2 D-isomerase (human) in blood.