A single gene, a plant leaf, the global climate: it's a huge shift upward in scale. Yet starting with the smallest building blocks of life must be part of Canada's strategy for addressing climate change. Nations are gathered at the United Nations conference on climate change (COP21) to seek global agreement on two fronts: taking action to reduce the greenhouse gas emissions that create global warming, and helping countries adapt to the impacts of climate change as they transition toward low-carbon economies. The actions Canada will take to realize its COP21 commitments must encompass a broad terrain of public policymaking. An estimated 35 per cent of global human-produced greenhouse gas emissions stem from energy production, 14 per cent from agriculture and 10 per cent from deforestation. All of these involve sectors of major importance to Canada, and each sector demands action not just to reduce emissions but also to mitigate and adapt to the effects of climate change. The promise of starting at the smallest level to tackle these largest-scale challenges is becoming clearer now that the science of genomics—which examines the genetic code and function of genes within the DNA of all living things—is maturing into practical applications. In the extractive industries sector, genomics holds the potential to help mitigate climate change. University scientists in Alberta have discovered microbes that have the potential to remove environmentally harmful tailing pond wastes left behind from oil sands; and in doing so, the microbes reduce greenhouse gas emissions from these wastes. By controlling microbe activity in tailing ponds, such research can benefit both local environments and the global environment too. In agriculture, climate change means that farmers around the world are facing drier and hotter climates as well as more crop pests and disease. With a global population expected to top 9.4 billion by 2050, current crop yields must double in order to meet the demand—and today's seeds won't suffice. That's why breeders are turning to genomics and plant genetics for solutions such as breeding plants with broader leaves that hold water better during drought. Canada's forestry sector needs trees that will thrive under changing climate conditions producing more extreme weather. Climate change is also linked to spreading tree diseases and pests that are destroying millions of hectares of trees. To meet those needs, British Columbia researchers are sequencing genomes of tree species from diverse West Coast climates in order to identify seedlings tolerant to drought, cold and heat. In another project, BC and Quebec researchers are using genomics to identify white spruce seedlings naturally resistant to the spruce budworm. These projects will both contribute to healthier forests and help reduce carbon emissions. Using genomics effectively in face of climate change calls for action across many sectors. These include mining and energy, farming and forestry, as well as the research labs and start-ups where genomic innovations are discovered and turned to use. Encouragingly, all new federal Cabinet ministers received mandate letters noting that progress on climate change is one of the government's key priorities. It's also encouraging that the Liberal election platform promised to make considerable investments to support innovation and clean technologies in natural resource sectors; to fund new Canada Research Chairs in sustainable technology; and to make decisions on fisheries and ecosystem management informed by scientific evidence about climate change. Together with our partners in the Canadian genomics enterprise, Genome Canada is funding research that will help the government in its aims. Today our country is a world leader in genomics thanks to sustained federal investments through Genome Canada—more than $1-billion since 2000, matched by co-investments from provinces, business, non-profits and international partners. Continuing to fund cutting-edge research in Canada is vital because only here will genomic researchers focus on uniquely Canadian dimensions of climate change. There are few countries with as much to gain from genomics as Canada. We have one of the largest, richest and most pristine environments on the planet, and all of us have a stake in supporting the science that will help protect those assets. Dr. Cindy Bell, Interim President and CEO, Genome Canada   Genome Canada is a federally-funded not-for-profit organization that invests in genomic science and technology and its translation into applications that produce social and economic benefits for all Canadians.