The case for GM food

Biofortified pro-vitamin A rice created by transgenic methods - the so-called Golden Rice I and Golden Rice II - are emblematic of the potential benefits of micronutrient-rich plants.

Some 127 million preschool children are vitamin A-deficient. Not only does this cause blindness in about 250,000-500,000 children, it is also detrimental to the immune system, promoting the deaths of about 6,000 children a day worldwide from infectious disease. Vitamin A deficiency plays a significant role in the global burden of disease from malaria, the global burden of disease from diarrhoea, and much of the global respiratory disease burden.

While welfare agencies have had significant success in supplementing the diets of poor families in developing countries with vitamin A, they have difficulty in reaching all nutritionally deprived children. For instance, in India, despite vitamin A supplementation programs, UNICEF reports that 57 per cent of children under 6-years of age still suffer subclinical vitamin A deficiency.

Rice naturally lacks vitamin A, meaning that millions of children are vitamin A deficient because they lack the resources to regularly supplement rice with other vegetables. GM rice varieties that provide pro-vitamin A in the grain, called Golden Rice, originated from the pioneering work of biologists Peter Beyer and Ingo Potrykus who transferred traits from daffodils and bacteria into rice plants that gave rice grain the ability to produce pro-vitamin A, the important vitamin A precursor and human nutritional source of vitamin A.

Great effort has gone into thoroughly testing their GM rice varieties to ensure this transgenic rice is suitable for use by farmers in developing countries. Significant contributions have been made by the plant technology company Syngenta, which has improved on the original work by Beyer and Potrykus.

In 2004 improved varieties of pro-vitamin A biofortified rice (now referred to as Syngenta Golden Rice I and containing about 6 ìg of pro-vitamin A per gram of rice grain) went through practical farm field trials in the US, supervised by Louisiana State University. Using conventional breeding methods, Golden Rice I varieties are currently being crossbred in India and the Philippines with local rice varieties. The charter of the Golden Rice Project is to ensure that pro-vitamin A enriched rice is made available to low-income farmers at no extra cost and that poor farmers would be free to sell this rice in local markets.

One of the difficulties faced by this humanitarian initiative is speculation spread by Greenpeace that exaggerates the amount of rice children would have to eat to get a benefit from Golden Rice. This exaggeration arises from ignoring progress beyond the initial development stage, the fact the recommended daily allowance (RDA) of vitamin A contains a safety margin that allows for three months reserve supply of the vitamin to be stored in the liver, and that nutritionally impoverished people need far less vitamin than the RDA to positively and dramatically affect their health. At 6 micro-g of pro-vitamin per gram of rice, typical daily rations of Golden Rice should have a significant impact on vitamin A deficiency.

Nutritional benefits of Golden Rice are easily distributed as all that is needed is contained within the seed, which can be passed on from farmer to farmer at little or no cost. No adverse health effects of pro-vitamin A-enriched rice, either actual or hypothetical, have been identified. The rice plant will be of an appropriate type for the local growth conditions and cultural preferences, and the rice requires no special fertiliser or resource that is not already used by white rice. Economic studies by economist Kym Anderson suggest that the potential welfare benefits of this rice to Asian counties would be $US15.2 billion per year.

In 2005, scientists from Syngenta announced a new GM rice, called Syngenta Golden Rice II, that produces 23 times more vitamin A-related nutrients than the first prototype. It seems likely that this new rice will deliver in one small 60g portion of rice an amount of pro-vitamin A that will meet the child’s recommended daily allowance of 300 micro-g, which takes any questioning of nutritional impact of this new technology off the agenda of the GM debate.

Given that 6,000 children a day die due to vitamin A deficiency, and that methods currently used to supplement diets are not reaching all malnourished children, unnecessary delays in getting Golden Rice into the hands of poor farmers constitutes a real hazard.

Significant delays have been created by anti-GM lobby organisations such as Greenpeace, who have consistently tried to create the impression that the Golden Rice varieties have inadequate content of vitamin A.

In countries with good standards of nutrition, the opportunities for health benefits from GM foods are different. However, there are several GM products in the research pipeline that should be very attractive to even the most choosy shoppers.