Funding was requested to identify MSX disease resistance genes in oysters to better understand the genetic mechanisms of host defense, which are poorly known in marine invertebrates. These genes or markers are valuable for studying host-pathogen interactions and predicting host population response. The team will collect and analyze pre-epizootic samples and establish a baseline population genetics signature of a natural population that is potentially about to undergo a heavy selective mortality by MSX. They will also collect samples as the epizootic progresses and after mortality has occurred to validate markers for MSX-resistance and document genetic changes caused by MSX outbreaks. The team has previously worked at this location through a NSF Ecology of Infectious Disease award and has already identified a set of genes/markers that are associated with resistance to MSX and/or Dermo. Because MSX and Dermo occurred together, they could not separate MSX from Dermo resistance. This MSX outbreak in Maine, where Dermo is negligible, provides a rare opportunity to do so and observe the timeline of a genetic response of the host population and possibly rapid development of resistance. This request was made through a Rapid Response Research Grant (RAPID) rather than through a regular proposal because a new outbreak of MSX disease, caused by water-borne protozoan parasite Haplosporidium nelsoni, is being observed in eastern oysters in Maine. The prevalence has reached 96%, and heavy mortalities are expected soon when water temperature increases this spring and summer. The study must be undertaken without delay in order to understand the genetic mechanisms of oyster defense to MSX disease and observe the timeline of genetic response and development of resistance of the host population. Broader Impacts of this proposal include participation of one graduate student. The study will take advantage of the new outbreak of MSX disease being observed in eastern oysters in Maine to understand the response of oyster populations to MSX disease. The results will be useful for understanding the consequences of future similar outbreaks.
|Effective start/end date||4/15/11 → 3/31/12|
- National Science Foundation (NSF)