The dysregulated genes Srebf1, Slc27a1, Foxo1 and Cpt1a that enriched in insulin resistance pathway also existed in the network of top 10 upregulated and downregulated node mRNAs (Figs. 3C and 3D), which indicating that these four genes might be important for the development of hyperglycemia and T2D in GK rats at the age of 3 and 4 weeks. This evidence concerns the gene FOXO1 and type 2 diabetes mellitus.