Due to the impairment of CD8+ T cell responsiveness to IL-7 in chronic infections [20, 21] and cancers [22], we sought to test the hypothesis that altered responsiveness to IL-7 in circulating and tumor-infiltrating CD8+ T cells and CD127 expression is one of the probable mechanisms for immune exhaustion in patients with primary cutaneous melanoma. The gene discussed is CD8A; the disease is cutaneous melanoma.