Molecular cloning of the breakpoint junction of a human chromosomal 8;14 translocation involving the T-cell receptor alpha-chain gene and sequences on the 3' side of MYC.
The MOLT-16 cell line, which was established from the malignant cells of a patient with T-cell acute lymphoblastic leukemia, is characterized by a translocation involving chromosome 8 (band q24) and chromosome 14 (band q11) [t(8;14)(q24;q11)]. To determine the position of the gene encoding the alpha chain of the T-cell receptor and of the protooncogene MYC (formerly c-myc) in relation to the breakpoint junction and to evaluate their possible role in the pathogenesis of T-cell neoplasia, we applied the techniques of in situ chromosomal hybridization, Southern blot analysis, and molecular cloning to MOLT-16 cells. Our results indicate that the breakpoint on chromosome 14 at band q11 occurs close to a joining sequence of the gene encoding the alpha chain of the T-cell receptor. The constant region and part of the joining region of this gene are translocated to the 3' side of the MYC exons. The breakpoints on chromosomes 8 and 14 are close to, but distinct from, those found in SKW-3, another T-cell leukemia cell line, which has a t(8;14). The identification of a breakpoint to the 3' side of MYC suggests that this recurring translocation is analogous to the variant t(2;8) and t(8;22) translocations observed in the B-cell malignancies.
D002460:Cell Line; D002874:Chromosome Mapping; D002901:Chromosomes, Human, 13-15; D002906:Chromosomes, Human, 6-12 and X; D003001:Cloning, Molecular; D006801:Humans; D007945:Leukemia, Lymphoid / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D011519:Proto-Oncogenes; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D014178:Translocation, Genetic
D011518:Proto-Oncogene Proteins; D011948:Receptors, Antigen, T-Cell