Molecular and cytogenetic analysis of the common chromosomal translocations in leukemia patients of Kerman

Background: Cancers of childhood are rare, but they are an important cause of morbidity and mortality in children younger than 15 years old. Leukemia is the most commonchildhood cancer. There are two main subtypes of leukemia include acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). A small portion may have chronicmyeloid leukemia (CML). Chromosomal abnormalities specific reciprocal translocations are the main causes of different types of leukemia. Most of the genetic abnormalitiescorresponded with leukemia can be detected by cytogenetic and molecular techniques such as fluorescence in situ hybridization (FISH), reverse transcription-polymerase chainreaction (RT-PCR), multiplex reverse transcription-polymerase chain reaction, DNA sequencing and microarray technology. Materials/Patients and Methods: We studied 75 patients with leukemia that they were referred to Dr.Bazrafshani Medical Genetics Laboratory from the Oncology Center of Kerman Afzali-pour Hospital in 2011-2012. Peripheral blood was collected in sodiumEDTA tubes. RNA was extracted from buffy coat. CDNA was produced by using Reverse Transcriptase enzyme and multiplex RT-PCR was performed on all samples. Also, karyotype were performed for all patients. Results: In all cases with different types, the multiplex RT-PCR method was able to detect 3 significant chromosomal translocations. In CML, 8(11%) children had t(9;22)(q34;q11), 5 children(7%) had t(1;19)(q23;p13) in ALL, and 3 of them had t(8;21)(q22;q22) in AML while karyotype could not detect any of them.Conclusion: This developed multiplex RT-PCR method can be applied to detect these three chromosomal translocations specifically and sensitively in spite of karyotype. Due to its accuracy and cost-effectiveness were preferred to karyotype in detection of common chromosomal translocations which cause leukemia.

Keywords:

Leukemia , Multiplex RT-PCR , Translocation , Karyotype