When the maximum [Ca2+]i levels obtained by treatment of PMNL with calcium ionophore A23187 and minimum [Ca2+]i levels obtained by quenching with EGTA and MnCl2, in fMLP and C5a stimulated normal and CML PMNL were compared, they were not significantly different. This evidence concerns the gene C5AR1 and chronic myelogenous leukemia, BCR-ABL1 positive.