Experimental Factor Ontology entry EFO_0009651 (rag2 deficiency) can be described as follows. Recombination activating gene 2 protein (also known as RAG-2) is a lymphocyte-specific protein encoded by RAG2 gene on human chromosome 11. Together with RAG1 protein, RAG2 forms a V(D)J recombinase, a protein complex required for the process of V(D)J recombination during which the variable regions of immunoglobulin and T cell receptor genes are assembled in developing B and T lymphocytes. Therefore, RAG2 is essential for generation of mature B and T lymphocytes. Also known as: RAG-2 deficiency, V(D)J recombination-activating protein 2 deficiency, recombination activating gene 2 deficiency.