We believe that the molecular events that occur in ALL can also occur in PTCL.In tumor cells, the control mechanisms which are responsible for preventingfurther restructuring of a locus after a productive rearrangement aredisrupted, which leads to increased activity of the RAG1 andRAG2 enzymes, changes in chromatin organization, etc. It ispossible that in PTCL rearrangements can be replaced with new ones and/or thatan incomplete Dβ–Jβ one can be replaced with a completeVβ–Jβ one. This evidence concerns the gene RAG1 and mature T-cell and NK-cell non-Hodgkin lymphoma.