A compound attribute that is the ratio of amount of interleukin-1 receptor type 2 (human) in blood to amount of multiple epidermal growth factor-like domains protein 9 (human) in blood. The trait is IL1R2/MEGF9 protein level ratio in blood (Ontology of Biological Attributes entry OBA_2054429). Also known as: the ratio of amount of interleukin-1 receptor type 2 (human) in blood to amount of multiple epidermal growth factor-like domains protein 9 (human) in blood.