Final answer:
During delta gene rearrangement, an additional DNA recombination event called 'additional diversity (D) rearrangement' can occur, resulting in even more diversity in the antibody repertoire.
Step-by-step explanation:
Rearrangement at the gamma and delta loci proceeds similarly to the alpha and beta loci, with one exception during delta gene rearrangement.
During the delta gene rearrangement, an additional DNA recombination event called 'additional diversity (D) rearrangement' can occur.
This D rearrangement happens after the V (variable) and J (joining) segment recombination, resulting in even more diversity in the antibody repertoire.