Inactivation of DAPK1 due to methylation is a cause of both familial and sporadic CLL, and hypomethylation of DAPK1 has been found in peripheral blood mononuclear cells (PBMCs) of healthy individuals (30); however, the relationship with hypomethylation in CLL is unclear. The gene discussed is DAPK1; the disease is B-cell chronic lymphocytic leukemia.