In the course of proteomic analyses aimed at identifying proteins potentially involved in the pathophysiology of hepatic diseases, we found that a specific peptide fragment of complement component 4 (C4) was significantly more abundant in HCV carriers with persistent normal ALT than in patients with chronic hepatitis [6], as well as more abundant in HCV carriers, regardless of ALT levels, compared to healthy controls. The gene discussed is GPT; the disease is liver disorder.