A compound attribute that is the ratio of amount of flavin reductase (NADPH) (human) in blood to amount of porphobilinogen deaminase (human) in blood. The trait is BLVRB/HMBS protein level ratio in blood (OBA_2053300). Also known as: the ratio of amount of flavin reductase (NADPH) (human) in blood to amount of porphobilinogen deaminase (human) in blood.