Possible explanations could be the different role of cytokines and immune response in HCV infection and the relatively small number of patients in CHC group; recently Eguchi et al. reported a significant association between high serum leptin level and IFN resistance in a subgroup of 50 patients with low viral load (< 100 MU/L) [31]. The gene discussed is LEP; the disease is cryohydrocytosis.