The copy number of AML1, ETO, WT1, p27, c- kit and the AML1-ETO fusion gene in AML1-ETO positive cells was counted.     ///    "In these 36 primary cases, 4 cases (11.1%) acquired additional AML1-ETO fusion signal, 3(8.3%) had additional AML1 signal, 4(11.1%) had additional ETO signal, 20(55.6%) had additional WT1 signal, 15(41.7%) had additional p27 signal and 14(38.9%) had additional c-kit signal. "