In future, we can focus more on the relationship between TLR7 gene polymorphism and the viral load, the immunosuppression progression and the T-cell count in patients with hepatitis C. Furthermore, an increasing number of evidence has demonstrated that B-cell lymphoproliferative disorders such as mixed cryoglobulinemia (MC) are related to HCV infection. The gene discussed is TLR7; the disease is hepatitis C virus infection.