SGER: Evolution of Major Histocompatibility Complex (MHC) Class I and II Genes in the American Crow (Corvus brachyrhynchos) Following an Epidemic of West Nile Virus

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

Schat 0104795 In 1999 West Nile virus (WNV) reached New York causing massive mortality in American Crows (Corvus brachyrhynchos). In Tompkins County crows have been studied since 1990, and blood samples for DNA extraction are available. Since WNV will most likely reach epidemic proportions in upstate NY in the summer of 2001, massive mortality can be expected among crows. This provides a unique opportunity to determine which individuals can survive infection with WNV and identify the genetic component of the resistance. Large numbers of crows will be captured in the 2000-2001 winter and blood samples will be obtained for DNA analysis and serology. DNA samples will be analyzed for differences in immune response genes by, thus providing the basis to study genetic diversity before and after the onset of the expected WNV epidemic. The hypothesis will be validated if crows surviving the WNV epidemic differ in allele frequencies of genes associated with immune responses. Although it is assumed that pathogens co-evolve with the ability of the host to mount effective immune responses, very few studies using natural populations have tested the validity of this hypothesis. In order to understand the risks to which populations are exposed when a new disease infects them, it is important to compare populations before and after they are exposed to the new pathogen.