Different evolutionary pathway of B*570101 and B*5801 (B17 group) alleles based in intron sequences.

Two theories about MHC allele generation have been put forward: (1) point mutation diversification and/or (2) gene conversion events. A model supporting the existence of both of these mechanisms is shown in this paper; the possible evolution of the HLA-B*570101 and HLA-B*5801 alleles (which belong to the HLA-B17 serology group) is studied. The hypothesis favoured is that gene conversion events have originated these alleles, because intron sequences are also analysed. Evolution by point mutation should only be accepted if flanking introns have also been sequenced.