Molecular diagnosis of bcr-abl fusion gene in CML patients using Multiplex-Reverse Transcreptase-Polymerase Chain Reaction

Abstract

Background: Chronic myeloid leukemia (CML) is a stem cell disorder results from chromosomal abnormality, Philadelphia chromosome (Ph), which arises from the reciprocal translocation of part of long arm of chromosome 9, in which proto-oncogene ABL gene (ablson) is located, to long arm of chromosome 22, in which BCR gene (break point cluster region) is located forming BCR-ABL fusion gene, a molecular marker of CML. The BCR-ABL gene can be detected using several molecular methods, including southern blotting, fluorescence in situ hybridization (FISH) and Reverse Transcreptase-Polymerase Chain Reaction (RT-PCR). For its simplicity, rapidity, and sensitivity, RT-PCR is one of the most common techniques used for analyzing whether a target gene is being expressed or not. Objective: This study was designed as a try to apply molecular techniques as conformational diagnosis of BCR-ABL gene and its variants in CML patients. Patients & Methods: Venous blood sample from 34 CML patients, 12 ALL patients, 1 AML patients, 1 CMML patient and 2 healthy individuals were collected. RNA was extracted from these samples using specific kit for this purpose. Molecular screening for the presence of bcr-abl in those samples was done using Multiplex-Single Step-Reverse Transcriptase-Polymerase Chain Reaction (M-SS-RT-PCR). Amplified products were electrophoresid in 1.5% agarose gel. Results: The results showed that all CML patients were positive for bcr-abl while all the others were negative for this gene. Conclusion: qualitative molecular diagnosis of bcr-abl using M-SS-RT-PCR considered as Conformational diagnosis for CML patients before starting treatment.Key Word: CML - BCR/ABL -Multiplex Reverse Transcreptase Polymerase Chain Reaction.