A total of 106 to 415 DAPI stained cells successfully transfected with hSIN3B, ETO homologues or AML1-ETO were analyzed. B-23 was used as a marker for nucleoli. A majority of these cells showed a nuclear signal. Nucleoli were visible in 11–20% of the cells (column 4 plus column 5). The ETO homologues showed a nucleolar localization in approximately half of these cells as. AML1-ETO showed no nucleolar localization.