One AID to Unite Them All

Abstract
By creating an extremely diverse antibody repertoire, B cells protect the body against numerous infectious pathogens. Generation of this antibody repertoire depends on immunoglobulin gene modification events driven by four different molecular processes: V(D)J recombination, somatic hypermutation, class switch recombination, and gene conversion. The enzyme AID (activation-induced cytidine deaminase) is known to be involved in somatic hypermutation and class switch recombination. In their Perspective, Fugmann and Schatz explain that AID is also essential for gene conversion ( Arakawa et al.) and discuss how AID could operate in these three quite different processes.