A compound attribute that is the ratio of amount of platelet-derived growth factor subunit B (human) in blood to amount of tumor necrosis factor ligand superfamily member 13 isoforms alpha/beta/gamma/4/5 (human) in blood. The trait is OBA_2053988 (PDGFB/TNFSF13 protein level ratio in blood). Also known as: the ratio of amount of platelet-derived growth factor subunit B (human) in blood to amount of tumor necrosis factor ligand superfamily member 13 isoforms alpha/beta/gamma/4/5 (human) in blood.