The Effects of Epidemic Dynamics on MHC Diversity
The major histocompatibility complex (MHC) is a cluster of genes found in most vertebrate genomes which includes several gene families whose proteins play an important role in the recognition of foreign antigens. Pathogen-mediated selection (PMS) is believed to be responsible for the extraordinary levels of MHC diversity observed in humans and many other vertebrate species. Although there have been many theoretical studies of the relationship between PMS and MHC diversity, most have not incorporated the selective impact of epidemiological dynamics. A new discrete time agent-based model of MHC evolution, which includes epidemic processes, is introduced. In our model, we consider a finite population of diploid hosts which can be infected by one or more pathogen species that differ in transmission rate, virulence and mortality rate. Both the MHC genes of each host individual and the antigen gene sequences of each parasite are represented by binary sequences which can change over time as the result of mutations. Matches between the host's MHC sequence and a parasite's antigen sequence accelerate recovery from an infection.
Nancy Hernandez Ceron- Purdue University
Anuj Mubayi- Northeastern Illinois University
Jay Taylor- Arizona State University