A compound attribute that is the ratio of amount of matrix metalloproteinase-9 (human) in blood to amount of phospholipid transfer protein (human) in blood. The trait is MMP9/PLTP protein level ratio in blood (OBA_2054581). Also known as: the ratio of amount of matrix metalloproteinase-9 (human) in blood to amount of phospholipid transfer protein (human) in blood.