Application Of Multiplex Reverse Transcription-Polymerase Chain Reaction In Acute Myeloid Leukemia

Objective:To investigate combined application of multiplex reverse transcription-polymerase chain reaction(RT-PCR)and karyotype analysis to the detection of clonal chromosomal aberrations in acute myeloid leukemia(AML),and explore the expression and distribution of fusion genes among the subtypes of AML.Methods:Multiplex nested RT-PCR was used to detect fusion genes and MLL gene rearrangements in 80 cases of acute myeloid leukemia(AML).Cytogenetic data were obtained from all of them by R or G banding techniques.Results:Fusion genes,including AML1/ETO,PML/RARα,PLZF/RARα,CBFβ/MYH11,MLL gene rearrangements(that is MLL/AF6,MLL/AF9,MLL/AF10,MLL/ELL),TLS/ERG,AML1/MDS1(EVI-1),were detected in 36(48.6%) patients by multiplex nested RT-PCR.In the 80 patients who received karyotype analysis,data were available in 74 patients and cytogenetic aberrations were detected in 34(45.9%)only of them.4 types of fusion genes such as AML1/ETO,PML/RARα,PLZF/RARα,CBFβ/MYH11 were detected in 45 patients with normal karyotype.The detection rate of clonal chromosomal aberrations was enhanced to 70.3% by combined application of multiplex RT-PCR and karyotype analysis.10 cases of AML with MLL gene rearrangements(MLL/AF6,MLL/AF9,MLL/AF10,MLL/AF17,MLL/ELL,MLL/MLL) were found in 77 AML patients(13.0%)by specially designed multiplex nested RT-PCR,including M2 in 1,M4 in 2 and M5 in 7 of the 10 cases.Conclusions:1 Multiplex RT-PCR is useful in detection of fusion genes associated with specific translocations in acute myeloid leukemia (AML) with normal karyotype. Multiplex RT-PCR combined with karyotype analysis can improve the detection rate of clonal chromosomal aberrations in AML;2 Screening of common fusion genes by multiplex RT-PCR is an important tool which could provide useful and reliable molecular genetic information for the diagnosis and treatment of leukemia;3 MLL rearrangement is commonly genetic alternation detectable in M4 and M5.Multiplex nested RT-PCR is a powerful technique in the detection of MLL gene rearrangement for tentativelly diagnosed AML.