⁃ Subjects with T2D and IGT had higher circulating myonectin concentrations than normal subjects.⁃ A 45-minute exercise period did not change circulating myonectin levels.⁃ Plasma myonectin does not change significantly with an oral glucose tolerance test, EHC, or lipid infusion (in young individuals). The gene discussed is ERFE; the disease is type 2 diabetes mellitus.