By crossing the TRP1-specific TCR transgenic mouse strain [19] onto the GILT-deficient background, we created Ag+GILT-/-Tg animals in which T cells specific for the melanocyte differentiation antigen TRP1 escape negative selection in the thymus and populate the periphery, but fail to protect from melanoma challenge (Fig 1a) and do not induce autoimmune vitiligo (Fig 1b) [22]. The gene discussed is TYRP1; the disease is melanoma.