Sequencing of the VHDJH region of the heavy chain (IgH) gene locus (deduced from the transcriptome) showed that both the large B-cell and the plasma cell types of lymphoid expansions were either monoclonal or oligoclonal (Table 1), thus indicating that the TRAF3/BCL2 double-tg mice develop lymphoid neoplasms. This evidence concerns the gene BCL2 and lymphoid neoplasm.