The amount of a protein mono-ADP-ribosyltransferase PARP11 when measured in blood serum. The trait is level of protein mono-ADP-ribosyltransferase PARP11 in blood serum (OBA_2042763, an Ontology of Biological Attributes term). Also known as: blood serum protein mono-ADP-ribosyltransferase PARP11 amount.