Comparing IFN-γ secretion in response to melanoma cells by Pmel-1 versus Pmel-1 x SLAMF6 -/- lymphocytes showed that cytokine production by the Pmel-1 x SLAMF6 -/- lymphocytes was significantly higher at all effector-to-target ratios (p=0.05, Figure 4A and B and Figure 4—figure supplement 1A and B). Here, SLAMF6 is linked to melanoma.