Despite the essential role of RBP4 in IR documented previously [4,5], we want to stress that the link between RBP4 and IR cannot be demonstrated in HCV infection, as the CHC cohort did not show any associations between RBP4 and HOMA-IR levels, no HOMA-IR level alteration was found in the SVR patients with the reversal of low RBP4 levels, and no differences of HOMA-IR levels were noted between the HCV core and non-HCV core transgenic littermates. The gene discussed is RBP4; the disease is cryohydrocytosis.