During T cell and B cell development, RAG2 works together with RAG1 to induce DNA rearrangement and assembly of antigen receptor coding segments. Defects in RAG2 gene lead to the complete lack of mature T and B lymphocytes and result in severe combined immunodeficiency (SCID). RAG2 also functions in chromosome binding through its unique plant homeodomain (PHD). Sequestration of recombination signal sequences (RSS) within the nucleosome by RAG2 prevents access by the recombinase complex.