Role of interleukin 28B rs12979860 C/T polymorphism on the histological outcome of chronic hepatitis C: relationship with gender and viral genotype.

BACKGROUND: This study aimed to determine whether the single-nucleotide polymorphism (rs12979860 C/T) of the interleukin 28B (IL-28B) gene, which is associated with hepatitis C virus (HCV) clearance, is also associated with fibrosis in chronic HCV infection. METHODS: An RFLP-PCR technique was used to genotype 629 HCV-positive patients (200 with cirrhosis) and 428 healthy control subjects. RESULTS: The genotype frequencies in the controls and chronic hepatitis C patients were as follows: C/C 47.0% vs. 32.6%, C/T 41.8% vs. 52.8% and T/T 11.2% vs. 14.6% (p < 0.0001). The C allele frequency was higher in HCV-2- (0.635) and 3- (0.692) infected patients in comparison to those infected with HCV-1 (0.550) or 4-5 (0.600) (p < 0.001). Infected T/T homozygotes had a mean staging score higher than other patients (3.50 vs. 3.04, p < 0.05). CONCLUSIONS: IL-28B rs12979860 C/T polymorphism is associated with a greater likelihood of HCV persistence, particularly in HCV genotypes 1 and 4. The T allele affects the severity of liver fibrosis.