PRV-Fa infection can lead to a large increase in the IL6 mRNA expression, whereas inoculation of PRV-ΔgE/ΔgI/ΔTK or PRV-ΔgE/ΔgI/ΔTK-(CD2v) did not cause up-regulation of IL6 expression (Fig. 4a). This evidence concerns the gene IL6 and Friedreich ataxia.