Data on the expression of several activating receptors such as NKp30, NKp46, DNAM-1, CD16 and killer-cell immunoglobulin-like receptors (KIR) on NK cells of CLL patients are inconsistent.13–17 One possible confounder that could explain inconsistent results on NK cell phenotype in CLL is cytomegalovirus (CMV) infection. This evidence concerns the gene FCGR3A and B-cell chronic lymphocytic leukemia.