Interleukin-4 polymorphisms and response to combination therapy in Egyptian chronic hepatitis C patients

In hepatitis C infection, the production of inappropriate cytokines levels may contribute to viral persistence and may affect the response to antiviral therapy. We investigate the effect of IL4 C–590T and C-33T polymorphisms on the response to combination therapy with interferon and ribavirin in chronic HCV patients. These single nucleotide polymorphisms were determined by PCR–RFLP in 235 responder and 210 non-responder to combination therapy. The IL4-590 T/T and -33 T/T genotypes were associated with resistance to the therapy (p < 0.001, p = 0.001 respectively). Haplotypes T(−590) T(−33) and T(−590) C(−33) were associated with a higher risk in non-responder patients than the responders (p < 0.001 for each) while frequency of haplotype C(−590) C(−33) (with all wild alleles) was significantly higher in responders as compared to non-responders (p < 0.001). These results suggest that inheritance of the IL4 polymorphisms may be associated with resistance to combined antiviral therapy in Egyptian HCV patients.