Genomics and food security

In my previous blog ‘A decade of the human genome’, I discussed some of the challenges encountered in exploiting genomics for human healthcare applications in the decade since the announcement of the sequencing of the human genome. I’d now like to focus on the impact of genomics on the challenges to food security caused by population growth and climate change.

Population growth is leading to critical challenges in areas such as:

• Food production: By 2030, the world will need to produce 50% more food to feed a global population of nearly 9 billion. Whilst agricultural productivity increased by 4% each year during the 'Green Revolution' of the 1960s and 1970s, this rate has now fallen to only 1% (http://www.soci.org/Chemistry-and-Industry/CnI-Data/2010/14). The magnitude of the challenges facing global food production is highlighted in the recent Royal Society report on food security (http://rstb.royalsocietypublishing.org/site/2010/food-security.xhtml).
• Water demand: Supplying the world with food demands a lot of water. Agriculture consumes about 70% of fresh water worldwide, with around 1,000 litres required to produce 1kg of cereal grain and 43,000 litres to produce 1kg of beef (http://caliber.ucpress.net/doi/abs/10.1641/0006-3568%282004%29054%5B0919%3ABTWBIT%5D2.0.CO%3B2).
• Climate change: Biofuels are a potential means of reducing CO2 emissions that contribute to global warming but first-generation biofuels (e.g. ethanol and biodiesel produced from food crops) have marginal environmental and economic benefits. Moreover, converting forest lands into bioenergy agriculture could accelerate climate change by emitting carbon stored in forests, while converting food agriculture lands into bioenergy agriculture could threaten food security.
• Land use: The Royal Society report also noted that the loss of potentially productive land due to soil erosion and contamination with salt, pollutants etc. is a major problem. It is estimated that there are around 400 million hectares of abandoned cropland globally (http://foodsecurity.stanford.edu/publications/the_global_potential_of_bioenergy_on_abandoned_agricultural_lands/).
  
  Examples of the potential use of genomics to address these challenges include the following:
• The Royal Society report looked at the potential to increase food crop yields and concluded that a large proportion of the yield increases that will be required to feed the world’s population must be delivered via plant breeders. They will need to make advances as quickly as in the past, if not faster, and they will therefore need all the tools that biotechnology can provide: genomics and bioinformatics are likely to be of paramount importance.
• The Royal Society report also looked at the potential of animal breeding to increase livestock productivity and to address other attributes such as product quality, increasing animal welfare, disease resistance and reducing environmental impact. Genomics is likely to have considerable impact in the future. For example, DNA-based tests for genes or markers affecting traits that are difficult to measure currently, such as meat quality and disease resistance, will be particularly useful. Genomic selection should be able to at least double the rate of genetic gain in the dairy industry, as it enables selection decisions to be based on genomic breeding values, which can ultimately be calculated from genetic marker information alone, rather than from pedigree and phenotypic information.
• Ceres, Inc. (http://www.ceres.net) is utilising genomics to develop low-carbon energy crops for advanced biofuels and biopower. In June this year the company announced that it has developed a plant trait that confers a high degree of salt tolerance on grasses, such as sorghum, miscanthus and switchgrass, which are highly productive sources of biomass feedstock for both biofuel production and electricity generation.
• Joule Unlimited, Inc. (http://www.jouleunlimited.com) is one of several firms working on single celled algae, tweaking their metabolic pathways to improve the rate at which CO2 is fixed by photosynthesis and then converted into hydrocarbons that can replace the petrol, diesel and kerosene used as fuels for cars and aircraft. The raw material used is potentially very cheap: the CO2 exhaust from power stations. The company currently has a pilot plant operating.
• Prof George Church of Harvard Medical School (http://arep.med.harvard.edu/gmc/) has developed a technology, multiplex-automated genomic engineering (‘MAGE’), which can rapidly engineer up to 50 genetic changes in bacteria, dramatically speeding the quest to design bacterial factories capable of efficiently producing drugs, biofuels, and other chemical products (http://technologyreview.com/biomedicine/22299/). He has been involved in the foundation of several companies, including Joule Unlimited, LS9 (http://www.ls9.com) and Microbia (http://www.microbia.com/) that are utilising MAGE to develop microbial processes for the manufacture of a range of industrial chemicals and fuels.
  
  These are major challenges, and opportunities, for society as a whole, and the genomics revolution can play a significant role. However, developing appropriate technology is just one part of the process of addressing these challenges. The biotech industry as a whole needs to ensure that it acts quickly and effectively to address issues such as dissemination of technology to the developing world, sharing of IP through business models that allow farmers and smallholders in these countries to access new crop varieties and livestock breeds etc.
  
  The international community also needs to act collectively to ensure that equitable incentives and policies for biofuel production and use are put in place, and that these measures do not impact negatively on food production and security.