Abstract：ObjectiveTo investigate the relationship between the subtypes of acute promyelocytic leukemia (APL) and expression of chromosome translocationt（15；17）or fusion gene of PML-RARa.MethodsFifty-five APL patients were studied in the research.APL subtypes were determined according to FAB classification.Conventional karyotype analysis was performed to study chromosome translocation t（15；17） and fluorescent in situ hybridization（FISH）was employed to detect PMLRARa fusion gene.ResultsAPL patients were classified into three subtpyes:M3a,M3b and M3c.The occurrence of t（15；17） and PMLRARa fusion gene were 82.61% (19/23）and 95.65%（22/23）in M3a,82.35%（14/17）and 94.12%(16/17)in M3b,80.00%（12/15）and 100.0%（15/15）in M3c respectively(χ2=0.046，P>0.05;χ2 =0.844，P>0.05).The expression of t(15;17) and PML-RARa fusion gene were 81.82%（45/55）and 96.36%(53/55) respectively (χ2=6.476，P<0.05).ConclusionsThere are no statistic differences between the the APL subtypes and expression of chromosome translocation t（15；17）or PML-RARa fusion gene.FISH may be a more sensitive technique than conventional karyotype analysis.
