The amount of a N-acetylated-alpha-linked acidic dipeptidase 2 when measured in blood serum. The trait is level of N-acetylated-alpha-linked acidic dipeptidase 2 in blood serum (Ontology of Biological Attributes identifier OBA_2042495). Also known as: blood serum N-acetylated-alpha-linked acidic dipeptidase 2 amount.