Gene Ecology versus Reductionism in Biology. Thomas Bøhn PhD Scientific Director, GenØk

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1 Gene Ecology versus Reductionism in Biology Thomas Bøhn PhD Scientific Director, GenØk

2 This talk Human as beaver Two contrasting knowledge systems Organisms are composed of traits coded by genes Understanding organisms in their context Examples: Transgenic wheat Transgenic maize Transgenic soy Transgenic mosquitos

3 Beaver activities - Cutting down a tree - Flooding the environment - Ecosystem engineering

4 The human beaver

5 When we cut trees

6 When we build dams

7 When we engineer ecosystems

8 When we do agriculture

9 When we engineer organisms Large scale Single event GM Roundup ready soybean planted on ~60 mill ha 2 billion sterile insects per week in one factory Knowledge DNA sequences, genetics, laboratory, construction Knowledge gaps Contextual knowledge in receiving environment Interactions in local food-webs Further spread and evolution

10 The Human as ecosystem engineer and beyond We change the external environment Transforming landscape into agriculture, cities, roads etc. Alter the environment through chemical pollution, global warming, introductions, etc. We change the organisms from within Breeding programs Genetic engineering/modern biotechnology

11 Genetic engineering using knowledge from the parts Bacteria Bacillus thuringiensis Plasmid vector gene ferry Bt-toxin (cry)gene cut AR Virus - CaMV paste CaMVpromoter cut CaMV + Bt paste AR Expression vector ferry with insert

12 Plasmids A Bt-toxin producing maize cell Cellwall Nucleus Gene gun Chromosomes AR AR Uncertainty: - Insertion site - Copy number - Fragments

13 Simple methods complex results Donor genes Gene ferry Transgenic plant - - CaMV + Bt paste AR Ferry with donor genes Introduced to: Recipient plant Ecosystem that interacts with this plant A dynamic agriculture Multiple cultural contexts

14 Approach to agriculture biotechnology and biosafety Reductionism DNA causing Traits causing Plants or other organisms in order to: Remove disease Remove pest insects Remove weeds Remove parasite/viruses that carry human diseases Insertional effects/epigenetics Transgene x environmental interactions Unintended effects on health and environment Evolution of resistance Uncertainty Sustainable production Gene Ecology

15 Example I: Transgene x environment interactions Transgenic fungus resistant wheat studied in glasshouse and in the field vs Four different events (same single gene/plant line) tested to see if unintended phenotypic effect could be traced (From Zeller et al. 2010)

16 (From Zeller et al. 2010) Role of environmental context Glass house Field

17 Example II: Bt-transgenic maize Bt-toxin produced in all cells throughout the lifecycle (~60 mill hectares) Consumers of plant will be exposed to Bt-toxins Specific killing of pest insects Biomass: Grain 18% Stover 29% Unharvestable 53% (Wilts et al 2004)

18 South Africa: evolutionary response in the pest insect Development of tolerance in pest insect when exposed to Bttoxin Buseola fusca

19 2004

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21 Response in South Africa to response of resistance Spraying with pesticides Stacking of several Bt-toxins Wider non-target effects Possible long-term negative effects on ecosystem services

22 Example III: Herbicide tolerant GM plants weed resistance 1. Herbicide use 2. Tolerant weeds 3. Increased use 4. Increased tolerance 5. Addition of other chemicals (more toxic) From Binimelis et al (2009)

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24 Example IV: GM mosquitos Purpose: cut the life-cycle of parasitic disease carriers (protozoa, viruses, helminths) Main disease-carrying mosquito groups: Anopheles that transmit malaria Aedes that transmit yellow-, dengue-, Chikungunyafever and West Nile virus

25 (From Terenius et al. 2008) Example IV: How well do we understand GM mosquitos? Considering the advances in both mosquito genomics and transgenesis, we are within reach of the creating an optimal genetically modified mosquito However we lack: Laboratory colonies for important species Logistics of field applications Knowledge on compatibilities between GM and wild type Control over dispersion Risk assessment Community desire and political will to try new disease control practices

26 Conclusions Two paradigms of knowledge meet in biosafety research 1. Product oriented engineering. Gene causes function. Understanding based on DNA. Organism as collection of traits. Host of gene not relevant. Environment less relevant. Secondary/system responses not in focus. Seed. Spray. Harvest. 2. Gene ecology. Genome-organism-environment interactions. Context matters. Context as cause: In gene expression patterns/function In phenotype evolution, e.g. resistance Greenhouse versus field, etc.

27 Thank you for your attention!