FCER2/FCRL1 protein level ratio in blood (OBA_2055362, an Ontology of Biological Attributes identifier) can be described as follows. A compound attribute that is the ratio of amount of low affinity immunoglobulin epsilon Fc receptor (human) in blood to amount of Fc receptor-like protein 1 (human) in blood. Also known as: the ratio of amount of low affinity immunoglobulin epsilon Fc receptor (human) in blood to amount of Fc receptor-like protein 1 (human) in blood.