Variable Antibody Genes
Following VDJ splicing additional diversity was found, which was first thought the result of splicing errors. Gene conversion was recently established as being subsequently responsible.
AID - (activation-induced cytidine deaminase) is required for gene conversion to occur in the V-region, but VDJ splicing will still occur without hypervariability.
Human immunity is due to single base-pair substitutions, found in 2002 to be gene conversion