title: Histocompatibility as adaptive response to discriminatory within-organism conflict: a historical model.
abstract: Multicellular tissue compatibility, or histocompatibility, restricts fusion to close kin. Histocompatibility depends on hypervariable cue genes, which often have more than 100 alleles in a population. To explain the evolution of histocompatibility, I here take a historical approach. I focus on the specific example of marine invertebrate histocompatibility. I use simple game-theoretical models to show that histocompatibility can evolve through five steps. These steps include the evolution of indiscriminate fusion, the evolution of discriminatory within-organism conflict, the evolution of minor histocompatibility, the evolution of major histocompatibility, and the evolution of major histocompatibility cue polymorphism. Allowing for gradual evolution reveals discriminatory within-organism conflict as a selective pressure for histocompatibility and associated cue polymorphism. Existing data from marine invertebrates and other organisms are consistent with this hypothesis.
authors.affiliation: Department of Integrative Biology, University of Texas, Austin, Texas 78712.
authors.forename: Owen M
authors.initials: OM
authors.lastname: Gilbert
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005716:Game Theory; D006648:Histocompatibility / Q000235:genetics*; D007448:Invertebrates / Q000235:genetics / Q000276:immunology*; D008957:Models, Genetic