A compound attribute that is the ratio of amount of N-acylethanolamine-hydrolyzing acid amidase (human) in blood to amount of sphingomyelin phosphodiesterase (human) in blood. The trait is Ontology of Biological Attributes term OBA_2054648 (NAAA/SMPD1 protein level ratio in blood). Also known as: the ratio of amount of N-acylethanolamine-hydrolyzing acid amidase (human) in blood to amount of sphingomyelin phosphodiesterase (human) in blood.