The amount of a beta-1,4-galactosyltransferase 1 (human) when measured in blood. The trait is Ontology of Biological Attributes id OBA_2052147 (amount of beta-1,4-galactosyltransferase 1 (human) in blood). Also known as: blood beta-1,4-galactosyltransferase 1 (human) amount.