Wednesday, 17 October 2012

Golden Rice: A GM crop designed to fight malnutrition

It is well known that there a lot of people in the world today who are malnourished. Unfortunately, this problem is actually two problems. The first is that people do not have enough food to eat. The second is that people don't have access to the right type of food. One of the most serious examples of this second problem is vitamin A deficiency. This post is the story of Golden Rice, a genetically modified (GM) crop designed to help prevent vitamin A deficiency. 

Vitamin A is an essential part of a healthy diet. Not having enough of it leads to night blindnessanemia, and a weakened immune system, with particularly bad effects in children and pregnant women. The effects on the immune system are particularly troubling since most of the countries that suffer from vitamin A deficiency also have high rates of infectious diseases. Vitamin A deficiency weakens a person's immune system leaving them vulnerable to these diseases. Infection with disease often then leads to a reduced appetite and reduced absorption of any vitamin A that is consumed, meaning that the person becomes even more vitamin A deficient, which in turn makes them even more vulnerable to disease. It is a vicious cycle.

The easiest way to get enough vitamin A is to eat animal products, but if the human body doesn't get enough from that source then it can also make its own vitamin A from another chemical, called beta-carotene. Beta-carotene is an orange-coloured pigment found in many fruits and vegetables - for example, it gives carrots their orange colour. When you eat fruit and veg that contains beta-carotene your body turns that beta-carotene into vitamin A. Unfortunately, there are many people in the world, especially in Africa and South Asia, who do not get enough vitamin A because their diet is not high in meat or vegetables. Instead, their diets are mainly based around rice, and while the rice plant itself does produce beta-carotene, it does so only in the leaves and stem. No beta-carotene is found in the grain (the part that people eat). This means that vitamin A deficiency is a big problem in these regions. Approximately one third of the world's preschool-age children are estimated to be vitamin A deficient and when only Africa and South-East Asia are considered, this figure rises to approximately 44-50%. It has been estimated that making enough vitamin A available to all of the world's children would prevent around 2 million child deaths per year.

This is where Golden Rice comes in. Golden Rice is a variety of rice that has been genetically modified to make it produce beta-carotene in the grain. Since beta-carotene is an orange pigment, this means that the rice grains are orange instead of white (as shown on the left in the picture below), which is where the name 'Golden Rice' comes from (okay, so orange and gold aren't quite the same colour, but I guess 'orange rice' would have sounded a bit rubbish).

Golden Rice grains (left) and normal rice grains (right)

At the moment, Golden Rice is still going through the regulatory process that all new GM crops have to go through. Once it is ready to be used, the seeds will be given to poor farmers around the world for free. It has been bred with local varieties in the regions that it is being given to, so that it has the same characteristics as the rice that people are used to. Farmers won't have to change their growing practices and consumers won't have to change their cooking habitsThe only difference will be that they will be getting a healthy dose of beta-carotene with each bowl of rice they eat. Just like normal rice, farmers will be able to reuse the seed from one harvest in order to grow rice for the next season. This means that the new seeds only have to be distributed to each region once. 

Although Golden Rice has not yet been given to any farmers, the project has been underway for at least twenty years. Scientists began working on it in 1992 and it was in 1999 that they first managed to produce rice that made beta-carotene in its grains. However, the levels of beta-carotene produced were considered too low. Although this rice would have provided more beta-carotene than normal rice, it did not have high enough levels to completely fulfill the needs of people who are eating little else than rice. The experiments continued and by 2005 the scientists had managed to get the beta-carotene up to a much higher level. It has been shown that about 100-150g of this new version of Golden Rice can provide about 60% of a child's daily vitamin A requirement. Since then, the rice has been going through various tests to prove that it is safe for people to eat and that it won't harm the environment. The people behind the project are currently working with regulators in some target countries and hope to transfer Golden Rice seed to some farmers in the next few years. 

Many of the people who work on the Golden Rice project feel that progress so far has been unnecessarily slowed down by excessive regulation of GM crops. One the plant's two co-inventors, Ingo Potrykus, wrote an article in the scientific journal Nature in which he argued that there is no logical reason for new GM crops to have to undergo any more tests than other types of new crop. He argues that the the current regulations on GM crops are putting unnecessary financial and time constraints on the development of crops that could otherwise be preventing death and suffering. 

There are others, however, who think that Golden Rice seeds should never be given to any farmers at all. For example Greenpeace, who are opposed to all GM crops, have written articles criticizing the Golden Rice project (for example, this one and this one). Not only do they think that the new rice is a dangerous, untested technology, they also feel that it is completely unnecessary given the other strategies that are available to combat vitamin A deficiency. 

In general, I tend to agree with the scientists from the Golden Rice project on these issues. However, a full discussion of my reasons for this would take a few more posts, and it is certainly something that I plant to write about in the future. For now though, I just wanted to present the basics of the story. Anyone who wants to read more about the Golden Rice project, or the science that enabled it should take a look at and anyone who wants to read some of the arguments being made against it should have a look at some of these articles: 

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