Ig heavy-chain gene revision: leaping towards autoimmunity

B cells can revise their antigen receptors outside the confines of the bone marrow by secondary Ig gene rearrangements. Although the initial motivatio n to perform these revisions might be to silence a self-reactive specificit y, those B cells that reinitiate the recombination process can perform a se ries of 'leaping' rearrangements and inadvertently shift their receptor spe cificity towards autoimmunity. Heavy-chain receptor revision, coupled with other atypical rearrangements, might contribute to autoantibody production in systemic lupus erythematosus.