Zurich researchers have developed a variety of rice containing up to six times more iron than normal white rice grains by adding in two extra genes.
The team at the Federal Institute of Technology in Zurich hope that their rice will help combat iron deficiency – a major global health problem – in developing countries.
According to the World Health Organization, iron deficiency anaemia is one of the most important contributing factors to the global burden of disease. Pregnant women and children are particularly vulnerable.
One of the most common causes is lack of iron in the diet. Rice, a food staple for around half of the world's population, contains iron, but mostly in the outer layers of the rice kernel. This causes a problem, said Christof Sautter, the Zurich project leader.
"In the tropical and subtropical climate the outer layers of the kernel become rancid very quickly during storage and are therefore removed by polishing. The rest of the kernel, which is eaten, contains largely starch and very little else," he told swissinfo.ch.
Scientists have been trying to increase the iron content in the rice kernel. But traditional breeding techniques have so far not worked.
Genetic modification, using a single gene to either improve iron storage or iron transportation in the rice plant, has also been tried with unsatisfactory results. So the Zurich scientists transferred two genes.
Six-fold increase
"We combined both transport and storage improvement with the result that we can now have up to six fold more iron content in the centre of the kernel," Sautter said.
The results of the research led by Sautter and Wilhelm Gruissem were published on July 20 in the online edition of the Plant Biology Journal.
The scientists are pleased about the new rice variety. The prototypes grown in greenhouses behave normally and show no negative effects on the environment, including the iron content of the soil, they say.
"The goal is to offer these plant lines at the end of development to small-scale farmers for free," Sautter said. There won't be any patent fees.
Distribution to farmers is, however, still many years away, as the prototypes are not yet suitable for agricultural development.
The next steps will need to be taken by a body such as the International Rice Research Institute in the Philippines or industry, explained Sautter.
Next steps
First the genes would have to be transferred to local varieties. "And then because it's a genetic engineering approach, there are all the safety studies which are required for deregulation and that's a time-consuming task. From the Golden Rice we know that it takes at least five to ten years," he added.
Vitamin A-rich Golden Rice, announced in 2000, was developed by another Federal Institute team and Freiburg University in Germany. The first field trials started in 2004 and are ongoing.
Many countries have regulatory requirements for testing genetically modified organisms. Furthermore, some non-governmental organisations have raised concerns about the possible effects of GMOs on health and the environment.
Sautter believes that people will increasingly accept GMOs. And although the rice's iron content is already nutritionally relevant, the team plans to increase it by 12-fold in the future, so that enough iron can be consumed in one meal.
Nutrition benefits
Those working in nutrition are aware of the benefits of biofortification – the name given to the process whereby plants are bred to have higher nutrient levels in the edible parts, either through conventional breeding and/or modern biotechnology.
Among them is the WHO, which has a programme working against iron deficiency anaemia and other micronutritional deficiencies such as vitamin A and iodine deficiency. The WHO's Micronutrients Unit is headed by Juan Pablo Pena-Rosas.
Pena-Rosas told swissinfo.ch via email that, in theory, biofortified crops and other methods, such as industrial fortification or supplementation, would improve the micronutrient status of those suffering a nutrient deficiency.
He added that those people would need to consume enough of the foodstuff to cover the nutritional gap between their food intake and individual requirements.
"However, much more work still needs to be done before the efficacy and effectiveness of these foods, such as the Zurich rice, are proven to reduce iron deficiency and iron deficiency anaemia."
According to WHO figures, 1.62 billion people are affected by iron deficiency anaemia worldwide, making it the most common global nutritional disorder.
The Zurich scientists hope that their rice could therefore offer a glimmer of hope in combating this far-reaching problem.
source:swissinfo.ch
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