A compound attribute that is the ratio of amount of C-C motif chemokine 18 (human) in blood to amount of retinoic acid receptor responder protein 2 (human) in blood. The trait is OBA_2054700 (CCL18/RARRES2 protein level ratio in blood). Also known as: the ratio of amount of C-C motif chemokine 18 (human) in blood to amount of retinoic acid receptor responder protein 2 (human) in blood.