Total IgM titers were unchanged between patients with hepatitis C and controls (167 versus 117 mg/dL, Fig. 5a, Additional file 4: Table S7) whereas total IgG levels were higher in patients with hepatitis C than in controls (1506 versus 1091 mg/dL, Additional file 4: Table S7). This evidence concerns the gene CD40LG and hepatitis C virus infection.