In our attempt to investigate the potential role of FA1 in insulin sensitivity and T2D of human subjects, we studied the chronic effect of dlk1/FA1 on insulin sensitivity, and lipid metabolism in myotube cultures established from lean, obese, and type 2 diabetic (T2D) (Gaster et al., 2002) subjects. The gene discussed is INS; the disease is type 2 diabetes mellitus.