This suggests that CD16 could be used as a biomarker to select for donors with highly potent Vδ2 T cells rather than functioning as an active receptor that enhances tumor killing, and that genetic introduction of CD16 to CD16Lo Vδ2 T cells may not recapitulate the heightened activity of Vδ2 T cells expanded from the CD16Hi donors. The gene discussed is FCGR3A; the disease is neoplasm.