Howard Hughes Medical Institute, The Children's Hospital, The Center for Blood Research, Boston, MA 02115, USA.
V(D)J recombination is of fundamental importance to the generation of diverse antigen receptor repertoires. We review our current understanding of the V(D)J recombination reaction and how it is regulated during lymphocyte development. We also discuss how defects in the mechanism or regulation of V(D)J recombination can lead to human disease.