Figure 6. V(D)J recombination: recognition errors.

Three types of recognition errors are shown. In (a), recombination occurs between an authentic RSS (black triangle, with its associated coding flank, shown as a white box) and a cRSS (green triangle) with its associated coding flank (orange box), located on a separate DNA molecule. Recombination produces a trans rearrangement, with a pseudo coding joint and a pseudo signal joint. In (b), the recombinase recognizes a pair of cRSS located on separate DNA molecules. These recombine, generating a reciprocal chromosome translocation. The two products bear a pseudo coding joint and a pseudo signal joint. In (c), the recombinase recognizes a pair of cRSS located on the same DNA molecule, and generates a deletion, forming a pseudo coding joint (retained on the chromosome) and an excised circle containing a pseudo signal joint.