WP5: Genetic Erosion and Genetic Pollution

Methodologies

Overall objectives

• Assessment of methodologies for

monitoring actual genetic erosion and

pollution

• Assessment of methodologies for

prediction of likely genetic erosion and

pollution in the future

Possible strategy for discussion

Identify accessions of wild species relatives that have been in storage without seed increase, for 20/30/40 years: with accurate passport information

Revisit collection sites, and where populations still exist, re-record passport data and sample seeds

Where populations no longer exist, collect from adjacent comparable sites

Identify control samples of germplasm in gene banks where similar sets of accessions have been in storage (without rejuvenation) for different periods of time (eg 10, 20, 30 years)

Undertake high throughput genotyping

Undertake analysis of population genetic parameters to determine genetic erosion

Discussion points for WP5 - I. MATERIAL • Which species and how many can we

realistically study?

• Over what time scale?

• Does suitable material exist in genebanks?

• Do suitable complementary populations still exist in the wild?

• Is it possible to identify populations vulnerable to pollution by modern/GM varieties?

Discussion points for WP5 - II. CAUSES OF EROSION

• Greater appreciation of some or all of the

underlying causes of loss?

• How to assess causes of erosion other than

by taking a few specific examples?

• How can we use ecogeography?

Discussion points for WP5 - III. MEASURING EROSION• How do we actually measure erosion?

• How reliable/convincing will population genetic parameters be?

• Estimators of – gene flow? – population differentiation?– diversity?– distribution of molecular variance?

Discussion points for WP5 - IV. MEASURING POLLUTION

• Direct methods?

• Available markers?

• Indirect methods?

Discussion points for WP5 - V. MOLECULAR MARKERS

• Need for high throughput?

• Which marker system(s) to choose?

• Do we need neutral markers?

• Do we need markers that will reflect loss of

adaptive variation?

Discussion points for WP5 - VI. NEW IDEAS

• Any other methods or approaches available?

• To form part of major discussion

Discussion points for WP5 - VII. GUEST SPEAKERS

• We can invite two or three key experts to

advise on these issues - who?

• Molecular marker expert - GENE MINE?

• Population geneticist (gene flow/population

structure)?

• GM/gene flow and genetic pollution?

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