In a previous study with HIV-transgenic (Tg) mice [20], excess BAFF was concomitant with an enlarged splenic marginal zone, altered GC reactions, increased extra-follicular responses and high anti-dsDNA Ab titers, similar to that reported for BAFF-Tg mice, which present a break in tolerance and autoimmunity [20,21]. This evidence concerns the gene TNFSF13B and Autoimmunity.