Plasma levels of inflammatory cytokines (IFN-γ, TNF-α and IL-10) were measured at enrolment in the study and revealed higher TNF-α levels among SM cases than UM ones [median content in pg ml−1 (IQ25–75) = 23.5 (0–142.5) vs 0 (0–8.2), P = 0.004], as shown in Table 6. The gene discussed is IFNG; the disease is systemic mastocytosis.