The amount of a coenzyme Q-binding protein COQ10 homolog A, mitochondrial when measured in blood serum. The trait is level of coenzyme Q-binding protein COQ10 homolog A, mitochondrial in blood serum (OBA_2041100, an Ontology of Biological Attributes entry). Also known as: blood serum coenzyme Q-binding protein COQ10 homolog A, mitochondrial amount.