C9orf72 and Insulin resistance: Moreover, the possible role of Cdc42 in the development of peripheral insulin resistance is evidenced by studies that have shown altered activity of Cdc42-related insulin signal transduction factors such as Cdc42 interacting protein-4 (CIP4) and G protein-coupled receptor kinase 2 (GRK2) in adipose tissue [211,246] and C9orf72 in the liver [247].