The amount of a adenine nucleotide translocase lysine N-methyltransferase when measured in blood serum. The trait is level of adenine nucleotide translocase lysine N-methyltransferase in blood serum (OBA_2044742, an Ontology of Biological Attributes term). Also known as: blood serum adenine nucleotide translocase lysine N-methyltransferase amount.