We can’t deny benefits of genetics
Potential advantages cannot be held back any longer if farming is going to move forward
WE have come a long way since Gregor Mendel, the father of genetics, was conducting his experiments on the garden pea at his monastery in Austria in the 1850s.
Now we have mapped the genome sequence of many species and have a clear idea how it determines characteristics. Interestingly, the wheat genome is among the most complex, five times longer than the human genome, and was only successfully sequenced in 2018.
Genetic engineering did not have an auspicious start.
There was talk of a gene being taken from the Arctic flounder, a fish living in cold water, and introducing it into an arable crop so it could be grown in cold weather. No wonder it was branded as Frankenstein Food by the tabloid media.
The American giant Monsanto was the first to exploit the technology by offering farmers ‘Roundup Ready’ soya bean seed in 1989.
By installing a gene from a bacterium into the seed, it made the plant resistant to the herbicide glyphosate, sold as Roundup. Thus a multinational developed the technology to sell seed and herbicide to increase its profits rather than bring the benefit to humanity that it potentially offered.
That gave GMOs, genetically modified organisms, as they became known, a bad name in some influential quarters.
The technology remains very tightly controlled in the European Union 30 years on.
As the science has developed, it has become split into two.
Transgenics is where genetic material is taken from one species and introduced into another – that is what is usually understood as GM.
Sysgenics is the manipulation of the existing genes, turning some off, increasing the dominance of others, to achieve desirable characteristics. This has become known as gene editing. In July 2018, the European Court of Justice ruled that gene editing was not distinct from transgenics and should be subject to the same regulation.
Speaking recently, the Secretary of State at Defra George Eustice described that ruling as wrong when judged by the scientific evidence.
Now that we are no longer a member of the European Union, that judgement is not binding in the UK and Defra is holding a consultation on the issue.
The consultation document makes clear that the results of gene editing could have been achieved by traditional breeding methods and that is the justification for allowing the technology.
To that extent, the approach would be recognised by Mendel even if the techniques may be more advanced.
Thus the proposal is that GEOs (genetically edited organisms) are treated differently to GMOs (genetically modified organisms), opening up the potential for huge gains in agricultural productivity and environmental protection.
Genetic research by scientists at top stations such as Rothamsted, John Innes, Roslin and the Sainsbury Laboratory at Cambridge is among the most advanced in the world.
We have been modifying genomes for decades using radiation or chemicals to change the genes and thus the characteristics of the target species.
Now that the genomes of the species used in agriculture are fully known, it is possible to change the sequence of the four bases on the chromosomes to impact upon characteristics such as disease resistance by means of technology.
It is now possible, for example, to produce potato varieties that are resistant to blight, cutting out the need for repeated sprays of fungicide.
Excitement is growing that major breakthroughs may be imminent in terms of providing nutrients for cereal crops. Legumes such as clover have nodules on their roots that contain symbiotic rhizobia bacteria that fix atmospheric nitrogen turning it into a form that can be used by the plant.
This means that applications of nitrate fertiliser are no longer required.
Another strand of research by the same team is attempting to enhance the relationship between plants and soil fungi. The fungi form ultra-fine filaments that can extract sources of phosphorus that are otherwise unavailable and exchange the nutrient for carbon from the plant.
This process has broken down as farmers apply phosphate which is absorbed by the crop negating the symbiosis.
To grow a potato variety that is resistant to potato blight, thus obviating the need for regular fungicide applications or to develop varieties of cereals or other crops that have nitrogen-fixing bacteria in nodules on their roots, has enormous potential to improve farm productivity while reducing the usage of fertilisers and pesticides.
In my view, we have been held back for far too long and we should exploit these techniques as soon as possible.
I also believe that we should allow some measure of transgenics provided that the two species concerned are closely related. To gain disease resistance by crossing a cultivated plant with its wild cousin seems entirely reasonable to me.
If we are to allow GM as well as GE, that will require further safeguards as the consultation document makes clear. There are also other implications, such as our trade relations with the EU, but we cannot deny ourselves the potential benefits any longer.