An analysis in human lymphomas of a Jα region involved in a C-MYC Jα translocation; Relationship with TCR alpha, beta, and gamma rearrangements

The D14S7 locus defines the breakpoint on chromosome 14 of a t (8;14) (q24;q11) present in the T-cell line KE37-R in which DI4S7 sequences translocate 3′ to the c-myc oncogene. It has been shown previously that DI4S7 rearranges specifically in some but not all T cell clones and in the present study we investigated the frequency and specificity of its rearrangements in human fresh lymphoma samples.DI4S7 rearrangements were extremely specific since they were detected in 3 out of 5 T-cell lymphoma samples positive for TCRβandγbut not in 17 miscellaneous non-T lymphomas, 4 non neoplastic lymphnodes as well as unstimulated and activated polyclonal T-cells. Most of the rearrangements were in the form of deletions that appear to involve large pieces of DNA since the segments detected by a V_αprobe were also deleted. Rearrangement of DI4S7 and V_α regions were detected in lymphomas with a cortical thymocyte phenotype, demonstrating that they appear quite early in the differentiation of T cells.