The importance of AID in the generation of high affinity IgG anti-dsDNA antibodies and subsequent development of lupus nephritis has been substantiated by Jiang et al. who demonstrated that lupus-prone mice deficient in AID lacked auto-reactive IgG anti-dsDNA antibodies, but produced high levels of IgM anti-dsDNA antibodies that was associated with a significant improvement in glomerulonephritis and survival compared to wild-type mice (21, 22). The gene discussed is AICDA; the disease is glomerulonephritis.