Association between IPTA gene polymorphisms and hematological abnormalities in hepatitis C virus-infected patients receiving combination therapy

Background/Aims: Hematological abnormalities during hepatitis C virus (HCV) combination therapy with pegylated interferon a and ribavirin often necessitate dose reduction. Variants of the ITPA gene have been reported to protect against anemia during the early stages of HCV combination treatments but have also been associated with larger decreases in platelet counts. We aimed to identify the association between specific ITPA gene polymorphisms and hematological abnormalities in patients undergoing HCV combination therapy. Methods: In this retrospective study, 175 patients treated with HCV combination therapy were enrolled at St. Martin De Porres Hospital in Taiwan between 2006 and 2012. Two single nucleotide polymorphisms (SNP) within or adjacent to the ITPA gene (rs1127354, rs6051702) were genotyped. We investigated the effect of ITPA gene variants on hematological abnormalities during the therapy. Results: The ITPA rs1127354 minor variants were significantly associated with protection against anemia at week 4 (p=1.86×10^-6) and with more severe decreases in platelet counts during HCV combination therapy. SNP rs6051702 was not associated with the hemoglobin decline to >3 g/dL at week 4 in our study (p=0.055). Conclusions: The ITPA SNP rs1127354 is a useful predictor of ribavirin-induced anemia in Taiwanese patients and may be related to more severe decreases in platelet counts during the early stage of HCV combination therapy.