level of guanine nucleotide-binding protein G(i) subunit alpha-1 in blood serum (OBA_2041747, an Ontology of Biological Attributes entry) is the amount of a guanine nucleotide-binding protein G(i) subunit alpha-1 when measured in blood serum. Also known as: blood serum guanine nucleotide-binding protein G(i) subunit alpha-1 amount.