The first experiment was designed to determine the basal activity of the PLCγ2 mutant S707Y in intact cells and to compare this activity to two PLCγ2 mutants mediating resistance to ibrutinib in CLL characterized before [17], PLCγ2R665W and PLCγ2L845F (Figure 1, left panel). The gene discussed is PLCG2; the disease is B-cell chronic lymphocytic leukemia.