After excluding 971 patients due to use of insulin or GLP-1 RA (n = 397), missing laboratory data (n = 87), a lack of liver ultrasound data (n = 416), and other liver diseases such as viral hepatitis, autoimmune liver diseases and drug-induced liver injury (n = 71), 765 patients with T2DM and NAFLD were finally enrolled. This evidence concerns the gene GCG and type 2 diabetes mellitus.