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Genetic Indicators Research Molecular Ecology Research Branch NERL. Overview- Genetic diversity within species Gene induction (expression) research Some considerations for transplanting genetically resistant organisms. Research Goals. GPRA-
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Genetic Indicators Research Molecular Ecology Research BranchNERL Overview- Genetic diversity within species Gene induction (expression) research Some considerations for transplanting genetically resistant organisms
Research Goals GPRA- • Goal 8.1.1 - By 2008, develop indicators and monitoring designs for a national stream and coastal survey. • FY00 APM - A draft report on the feasibility of genetic and molecular biomarkers as an indirect measure of pesticide, toxics, and metals exposure to fish in the Eastern Cornbelt Plains ecoregion.
Genetic Diversity Indicator • Indicator of population sustainability
Genetic Diversity Indicator • Indicator of population sustainability • The ability of an organism to adapt to changing environmental conditions is dependent on genetic variation
Genetic Diversity Indicator • Indicator of population sustainability • The ability of an organism to adapt to changing environmental conditions is dependent on genetic variation • For small, threatened populations, inbreeding increases the probability of extinction
Genetic Diversity Indicator • Indicator of population integrity
Genetic Diversity Indicator • Indicator of population integrity • Forces that influence genetic diversity (selection, mutation, migration, drift) do so through their effects on populations • Dispersal • Population size • Reproductive success
Genetic Diversity Indicator • Indicator of population integrity • Forces that influence genetic diversity (selection, mutation, migration, drift) do so through their effects on populations • Can estimate key population parameters with genetic information • Effective population size • Effective migration rates
Genetic Diversity Indicator • Indicator of population integrity • Forces that influence genetic diversity (selection, mutation, migration, drift) do so through their effects on populations • Cumulative indicator of condition
DNA Fingerprints 1 2 HCV HS SM TD PL PLO MS Z B K
Genetic Diversity Indicator Major Products- • Regional genetic diversity profile for populations of the central stoneroller in the Eastern Cornbelt Plains Ecoregion • Report by end of the year
Genetic Diversity Indicator Major Products- • Regional genetic diversity profile for populations of the central stoneroller in the Eastern Cornbelt Plains Ecoregion • Regional multi-species genetic diversity profile for mid-eastern US. • Report for stonerollers by end of next year
Genetic Diversity Indicator Other Projects- • Genetic diversity profile for creek chubs in the coal-bearing regions of WV, VI
Genetic Diversity Indicator Other Projects- • Genetic diversity profile for creek chubs in the coal-bearing regions of WV, VI • Genetic structure of mummichog populations adapted to high concentrations of PAHs. • Collaboration with NHEERL- Narragansett
Gene Expression Indictor • Diagnostic indicators of exposure
Control of Gene Expression NUCLEUS CYTOSOL protein translation activity control control primary RNA 3 4 inactive protein DNA transcript mRNA mRNA protein 1 2 transcriptional RNA nuclear pore control processing control nuclear envelope
Gene Expression Indicator • Diagnostic indicators of exposure • Detect ‘first cellular event’ following exposure
Gene Expression Indicator • Diagnostic indicators of exposure • Detect ‘first cellular event’ following exposure • Highly sensitive to even trace materials
Gene Expression Indicator • Diagnostic indicators of exposure • Detect ‘first cellular event’ following exposure • Highly sensitive to even trace materials • Highly diagnostic of exposure to specific classes of stressors
Molecular methods have been developed to detect changes in: • Vitellogenin gene expression • Exposure to estrogenic compounds • Cytochrome P450IA1 gene expression • Exposure to PAHs • Metallothionein gene expression • Exposure to metals
Major Products • Estrogenic compound indicator • Method in place for rainbow trout, fathead minnow • PAH indicator • Method under development through cooperative agreement • Metals indicator • Method in place for rainbow trout
Estrogenic Activity indicator control 0.01 0.10 0.33 0.33 0.33 Vitellogenin 18S rRNA
Some considerations regarding transplantation of adapted organisms and communities
Transplantation Issues • Is the population really adapted to mining impact area? • Adaptation or acclimation? • Bioavailability differences between sites? • Adapted to same or different stressor profiles?
Transplantation Issues 2. Will the mitigation create new problems? • Will the transplants interbreed with nearby locally adapted populations? • Will the population need constant supplementation? • Will an artificial selection program need to be created?
Transplantation Issues 3. Research need: an ability to predict population responses to stressors: acclimation, adaptation, or extinction Depends on: • Magnitude and novelty of stressor • Number of genes involved in response • Genetic diversity of response genes • Rate of environmental change
Possible contributions by EPA genetics researchers • Assessment of bioavailability differences between sites • Metallothionein gene expression • Assessment of population structure/ gene flow within region • Most appropriate transplant populations • Potential for introgression with native stocks • Monitoring of population status