9418046 Vincek The major histocompatibility complex (Mhc) is one of the key elements the clonal immune response that protects advanced vertebrates from parasites. Because of its central role in an individual's immune response, the Mhc has been studied extensively by immunologists and geneticists. However, the information concerning its evolution is rather scant. Whether the Mhc and indeed clonal immunity, exist in primitive vertebrates, non-vertebrate chordates, and invertebrates is not known. The question of the emergence of immunity in phylogeny is of considerable interest because if alternatives exist to the immune response protecting advanced vertebrates, they may not be without significance to humans. %%% The isolation and characterization of Mhc genes from zebrafish will provide valuable information concerning the primordial function of the Mhc, and increase our knowledge regarding the evolution of immunity. ***
