Original Research Article
Year: 2016 | Month: November | Volume: 6 | Issue: 11 | Pages: 52-56
Identification of Chromosomal Translocations in Childhood Leukaemia Using Multiplex RT-PCR: A Single Institution Study in Multi-Ethnic Malaysia
Nor Rizan Kamaluddin1*, Yuslina Mat Yusoff2*, Ezalia Esa2*, Eni Juraida Abdul Rahman3**, Azli Ismail4*, Geik Yong Ang5#, Choo Yee Yu5#, Kok-Gan Chan6#, Zubaidah Zakaria7*
1Senior Research Officer, 2Haematopathologist, 3Consultant Paediatric Hemato-oncologist, 4Research Officer, 5Research Assistant, 6Senior Lecturer, 7Consultant Haematopathologist and Head of Department,
*Haematology Unit, Cancer Research Centre, Institute for Medical Research, Kuala Lumpur, Malaysia.
**Paediatric Institute, Hospital Kuala Lumpur, Malaysia.
#Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaysia.
Corresponding Author: Yuslina Mat Yusoff
ABSTRACT
Background: Leukaemia accounts for 48% of all childhood cancers in Malaysia. Recent advances in genomics have contributed significantly towards a better understanding of the genetic landscape of leukaemia. Identification of recurrent chromosomal translocations which can be detected in a substantial number of these patients are important for classification of the disease, prognostication, treatment monitoring and also to guide targeted therapy.
Objective: This study aims to report the incidence of leukaemia-specific translocations in Malaysian children who were admitted in tertiary care hospital from 2008 to 2011.
Materials and Methods: A total of 229 bone marrow or peripheral blood samples were collected from children who were newly diagnosed with leukaemia. Their demographic data, bone marrow morphology and also immunophenotyping results were recorded. Multiplex reverse-transcriptase polymerase chain reaction (RT-PCR) was performed using the Hema Vision 28N protocols for detection of 28 common translocations.
Results: Among the 229 children, 162 patients were diagnosed with Acute Lymphoblastic Leukaemia (ALL), 52 Acute Myeloid Leukaemia (AML) and 15 Chronic Myeloid Leukaemia (CML). We found that 26.2% of these patients have chromosomal translocations. Overall, 10 fusion gene transcripts and 15 different splice variants were detected. The most common genetic abnormalities found were BCR-ABL1 8.3%, ETV6-RUNXI 7.0% and TCF3-PBX1 2.6%. Conclusion: Multiplex RT-PCR is an effective and rapid screening tool for detection of recurrent chromosomal translocations in childhood leukaemia. A comprehensive sub grouping of leukaemia by molecular technique is very useful not only for diagnostic purpose, but also for risk assessment, prognostication and personalised treatment.
Key words: Chromosomal translocations, Multiplex PCR, Childhood leukaemia.