We also assessed whether IL-17C, IL-17E and IL-17F could modulate the production of type I collagen, but we could not detect any significant change in HD and SSc fibroblasts (Figure 5), although a trend to increased collagen production was observed with the highest dose of IL-17E (600 ng/ml) in HD rather than SSc. The gene discussed is IL17F; the disease is Huntington disease.