https://www.rothamsted.ac.uk/news/gm-field-trial-planned
Rothamsted Research seeks permission from the Department for Environment, Food & Rural Affairs for the release of genetically modified Camelina plants for up to three years.
“Genetic Improvement of Camelina Seeds” is the title of the field trial that Rothamsted Research hopes to begin this year and complete by 2020, following its application this week to Defra for permission for “the release of genetically modified higher plants” on two of its sites, in Hertfordshire and Suffolk. The institute has previously field trialled Camelina plants that have been engineered to accumulate omega-3 long chain polyunsaturated fatty acids (LC-PUFAs), EPA and DHA, also the ketocarotenoid astaxanthin, in their seeds. This work and the currently proposed project are part of ongoing strategic programmes of research at Rothamsted.
In its formal description of the proposed project, Rothamsted notes that Camelina is an oilseed crop of the Brassicaceae family, whose useful properties include being amenable to genetic improvement. The seed oil of this crop has been modified to accumulate the health-beneficial fatty acids EPA and DHA, normally found only in omega-3 fish oils. Similarly, the seeds of this plant have been modified to accumulate either ketocarotenoids or wax esters, both useful compounds of otherwise limited availability. In addition, two traits related to plant architecture and photosynthetic capacity will be evaluated in the field, with the goal of improving Camelina as a crop.
Omega-3 LC-PUFAs have been shown to be beneficial for human health and contribute to protection against coronary heart diseases. The primary dietary sources of these fatty acids are marine fish, either wild stocks or farmed fish (aquaculture). Fish, like humans, do not produce these oils but accumulate them through their diet in the wild or through fishmeal and fish oil in farmed fish. Around 80% of all fish oil is consumed by the aquaculture sector. Aquaculture, a rapidly expanding modern industry, is seeking new sources of omega-3 LC-PUFAs to ensure its production practices remain sustainable and to nurture the essential aquatic food web. One potential approach is to engineer a crop plant with the capacity to synthesise the fatty acids.
“The omega-3 LC-PUFAs that are beneficial for health are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA),” says Johnathan Napier, Leader of the Omega-3 Camelina Flagship at Rothamsted and visiting professor at the universities of Stirling and Nottingham.
Napier continues: “Plant sources of omega-3, such as flax seed, do not produce EPA and DHA; instead they produce shorter chain omega-3 fatty acids, such as a-linolenic acid (ALA). ALA does not confer the health-beneficial properties associated with EPA and DHA, despite the former also being an omega-3 fatty acid. Not all omega-3 fatty acids are equivalent.”
He adds: “We used synthetic gene sequences involved in the biosynthesis of omega-3 LC-PUFAs and other useful traits, such as astaxanthin and wax esters, that have been optimised to be functional in Camelina plants. These synthetic sequences are based on the sequence of genes found in a range different organisms including photosynthetic marine organisms and other lower eukaryote species, such as mosses and oomycetes. By using transgenic Camelina as a chassis to make these useful lipids, we have an alternative source for them.”
For more information on this work, go to the impact story, “From oceans to fields and back again”, or go the 2016 report, “Flagship Project: Omega-3 Camelina Development”.