Studies of chickens have provided serological and nucleic acid probes useful in defining the major histocompatibility complex (MHC) in other avian species. Methods used in detecting genetic diversity at loci within the MHC of chickens and mammals will be applied to determining the extent of MHC polymorphism within small populations of ring-necked pheasants, wild turkeys, cranes, Andean condors and other species. The knowledge and expertise gained from working with the MHC of the chicken should make for rapid progress in defining the polymorphism of the MHC in these species and in detecting the polymorphism of MHC gene pool within small wild and captive populations of these birds. Genes within the major histocompatibility complex (MHC) are known to encode molecules that provide the context for recognition of foreign antigens by the immune system. Whether a given animal is able to mount an immune response to the challenge of a pathogen is determined, in part, by the allelic makeup of its MHC. In many species, an unusually high degree of polymorphism is maintained at multiple loci within the MHC in freely breeding populations. The allelic pool within a population presumably provides diversity upon which to draw in the face of environmental challenge. The objective of the proposed research is to extend ongoing studies of the MHC of domesticated fowl to include avian species experiencing severe reduction in population size. Knowledge of the MHC gene pool within populations and of the haplotypes of individual animals may be useful in the husbandry of species requiring intervention for their preservation.
