CALCOCO2 and diabetes mellitus: The ubiquitin-proteasome system has been suggested to play a role in the process of insulin resistance [7] and diabetes [8], making this locus of particular interest considering the close proximity of other ubiquitin-related genes like SNF8 and CALCOCO2. Another candidate target gene at this locus is GIP, which encodes for a potent stimulator of insulin secretion from pancreatic beta cells following food ingestion and nutrient absorption.