A compound attribute that is the ratio of amount of plexin-A4 (human) in blood to amount of Src kinase-associated phosphoprotein 2 (human) in blood. The trait is OBA_2053521 (PLXNA4/SKAP2 protein level ratio in blood). Also known as: the ratio of amount of plexin-A4 (human) in blood to amount of Src kinase-associated phosphoprotein 2 (human) in blood.