Aim: To establish a new method which analyzes T cell receptor (TCR) gene rearrangement for identification of T cells acute lymphoblastic leukemia (T-ALL) clone, it will provide the basis for the study of T-ALL including the chromosome translocation involving TCR loci.
Methods: Total DNA was isolated from peripheral blood mononuclear cells (PBMC) of one case with T-ALL. Using the fine-tiling array comparative genomic hybridization (fine-tiling aCGH) to analyze the genomic DNA differences of the case and control group, we could find the breakpoints and their position in the chromosomes. According to the preliminary results, we could design the specific primers for the positions of the breakpoints relative to sequence. Furthermore, the ligation-mediated PCR (LM-PCR) and sequence analysis were used to identify the TCR gene rearrangement. And TCR gene expression was detected by RT-PCR.
Results: The fine-tiling aCGH results of the T-ALL showed that the TCRα/δ locus of chromosome 14 appeared four breakpoints, corresponding to TCR Vδ1, Vδ2, Jδ1 and Jδ2. By LM-PCR, sequencing and sequence analysis, TCR gene of the case of T-ALL was involved in Vδ1Dδ2Dδ3Jδ1, Vδ2Dδ3Jδ2 rearrangement. RT-PCR results also confirmed the expression of these TCR gene rearrangements.
Conclusion: The results demonstrated that fine-tiling aCGH and LM-PCR techniques could be used to identify the TCR gene rearrangement as one of the best perfect methods. And it was also a way to find some fusion genes involving in TCR gene.