INS and type 2 diabetes mellitus: In support of a role for Sfrp5 in impairing insulin action are data from a clinical study on obese subjects without diabetes in which circulating Sfrp5 levels were found to be associated with HOMA-IR (r = 0.32, p<0.05) [14], and a study on Chinese subjects which reported increased circulating Sfrp5 levels in patients with T2D compared to subjects without diabetes [13].