IL4 and infection: To our knowledge, this is the first reported association study of IL-4 T + 33C polymorphism and spontaneous viral clearance in hepatitis C. During the course of hepatitis C, the IL-4 (+33) T allele is associated with higher expression of IL-4 gene[17] and with recurrence of infection after liver transplantation due to hepatitis C and more severe hepatic lesion[18].