As a result, cancer is associated with T-cell deletion and a defective T-cell memory repertoire, which includes anergic CD8+ T cells (hyporesponsive state upon low co-stimulation or high co-inhibitory stimulation) and exhausted CD8+ T cells (decreased cytokine expression and effector function upon chronic activation), as recently reviewed (2, 3). The gene discussed is CD8A; the disease is cancer.