Promising biomarkers, which are related to NASH and may help differentiate steatosis from steatohepatitis, are cytokeratin-18 (CK-18) [129], the terminal peptide of procollagen III (PIIINP) [130], IL-6 [131], TNF-α [132], the chemokines MCP-1 and RANTES [133], and fibroblast growth factor 21 (FGF21) [134]. The gene discussed is FGF21; the disease is steatosis.