Constitutive phosphorylation of ERK1/2 in the absence of AKT activation, constitutive phosphorylation of MEK1/2 and NFAT2 overexpression were described to be associated with attenuated BCR signalling upon αIgM treatment in a subset of human CLL patients11. This evidence concerns the gene MAPK3 and B-cell chronic lymphocytic leukemia.