A compound attribute that is the ratio of amount of bis(5'-adenosyl)-triphosphatase (human) in blood to amount of phosphoribosyltransferase domain-containing protein 1 (human) in blood. The trait is Ontology of Biological Attributes id OBA_2055399 (FHIT/PRTFDC1 protein level ratio in blood). Also known as: the ratio of amount of bis(5'-adenosyl)-triphosphatase (human) in blood to amount of phosphoribosyltransferase domain-containing protein 1 (human) in blood.