Simultaneous Reverse Transcription-Polymerase Chain Reaction for Detection of 7 Gene Rearrangements in Acute Leukemia

Kim, Kyeong Hee; Han, Jin Yeong

Abstract

Background
The diagnosis of acute leukemia is multidisciplinary with histology, immunology, and cytogenetics. Among these, cytogenetics is important for diagnosis and analysis of prognosis and some of the chromosomal abnormalities are specific for the particular subtypes of acute leukemia. However, cytogenetic analysis is laborious and sometimes does not provide sufficient metaphases. To detect the common 7 gene rearrangements in acute leukemia, a reverse transcription-polymerase chain reaction (RT-PCR) was performed simultaneously under the same conditions.
Methods
The author analyzed 38 cases of acute myeloid leukemia (AML) and 20 cases of acute lymphocytic leukemia (ALL) for the evaluation and treatment of acute leukemia. The simultaneous RT-PCR assays were performed under the same conditions to detect 7 chromosomal abnormalities of t(1:19), t(8; 21), t(9; 22), dupMLL (11q23), t(12; 21), t(15; 17), and inv(16) in acute leukemia.
Results
The simultaneous RT-PCR assay detected the expression of 7 fusion genes generated by chromosomal rearrangement. The gene rearrangements were found in 53% of AML and 40% of ALL. In AML, there were 7 cases of PML/RARA, 6 cases of AML1/ETO, 4 cases of dupMLL, and 3 cases of CBF/MYH11. In ALL, 4 cases of dupMLL, 2 cases of BCR/ABL, 1 case of E2A/PBX1, and 1 case of TEL/AML1 were detected. The discrepant results between simultaneous RT-PCR and cytogenetic analysis were found in 11 cases. Nine cases were positive by simultaneous RT-PCR but negative in the cytogenetic analysis and each case of variant t(9; 22) and t(15; 17) was negative in simultaneous RT-PCR.
Conclusions
It suggests that the simultaneous RT-PCR assay is an efficient and fast procedure for the detection of genetic changes in acute leukemia and it appears to be an useful method for rapid diagnosis of acute leukemia.