A 32-base pair deletion in the CC-chemokine receptor 5 gene (CCR5), associated with resistance to human immunodeficiency virus type 1 (HIV-1) infection, has recently been suggested to act as an adverse host factor in hepatitis C virus (HCV) infection. To examine this hypothesis, we determined the CCR5-Delta32 allele frequency by polymerase chain reaction in a Belgian cohort of 163 HCV-infected patients and 310 healthy control subjects. The resulting CCR5-Delta32 allele frequencies were 0.080 and 0.119 for the patient group and control group, respectively. In contrast with a previous study, we could not show a statistically significant difference between the CCR5-Delta32 allele frequencies in HCV patients and controls. Moreover, genotype distributions in both populations were in agreement with Hardy-Weinberg equilibrium. Our results do not support the hypothesis that the CCR5-Delta32 mutant allele is a risk factor for hepatitis C virus infection.