The amount of a glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1 when measured in blood. The trait is Ontology of Biological Attributes identifier OBA_2051452 (level of glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1 in blood). Also known as: blood glycosylphosphatidylinositol-anchored high density lipoprotein-binding protein 1 amount.