Where's the Super Food?
News Sep 01, 2009
- Bob Grant, The Scientist, Vo. 23, p 30. Full article at
Watch the related video at http://www.youtube.com/watch?v=Vxt52pUYROg
Right now, one billion people are starving. That’s one in every six people on this planet. The number of these hungry people is roughly equivalent to the populations of the United States, Indonesia, Brazil, Pakistan, and Bangladesh combined.
The world reached this bleak milestone in the middle of June this year. With the global human population continuing to explode and resources being stripped at an increasing rate, the outlook is not good. More people will go hungry. Less will have access to the nutrients their bodies need. And more will succumb to the illnesses that take advantage of the malnourished body. More people will die.
But this is only half the story. The insidious corollary to the global hunger crisis is that even more people—at least half the world’s population, according to a 2004 United Nations report—suffer from micronutrient malnutrition. People suffering from this “hidden hunger” may consume sufficient calories, but lack suitable amounts of essential nutrients, vitamins, and minerals. These legions of nutrient-starved people largely reside in developing countries. Their plight is dire. Even mild micronutrient deficiencies can increase infant mortality rates and lead to cognitive impairment and immune system problems in children, among other serious health issues.
In addressing global hunger and micronutrient malnourishment, biotechnology holds potential solutions: specifically, nutritionally enhanced, transgenic crops. The technology that makes these plants possible took center stage in January 2000 with the publication of a brief but high-impact Science paper on the creation of a prototype that would become known as “Golden Rice,” packed with beta-carotene (also called pro-vitamin A), the precursor to vitamin A and an essential component of healthy diets.1 Genetically modified (GM) crop plants were already becoming commonplace, but existing genetic changes mostly endowed plants with desirable producer traits, such as herbicide or pest resistance in soybeans or cotton plants. To create Golden Rice, European scientists, with funding from the Rockefeller Foundation, inserted bacterial transgenes into the latent pro-vitamin A biosynthesis molecular pathways in wild-type rice, which contains no pro-vitamin A. This modification transformed the normally nutrient-poor endosperm—or kernel—of milled rice into a source of beta-carotene.
Their work was trumpeted on the cover of TIME magazine with the headline: “This rice could save a million kids a year,” preventing night blindness and other disorders caused by low vitamin A, a nutrient often lacking in developing world diets. While it got people talking and thinking about the potential of genetic engineering to salve the world’s hunger pangs, Golden Rice also set up a contentious debate that still rages today. “[Golden Rice] was something that attracted the attention of both opponents and proponents in the same way,” recalls Peter Beyer, a plant biochemist at the University of Freiburg in Germany and one of Golden Rice’s inventors.
Nutritionists took Beyer and his co-inventor, now-retired biologist Ingo Potrykus, to task, pointing out that Golden Rice could do little to address vitamin A deficiencies in the developing world because its beta-carotene content was too low. Beyer says that anti-GM groups “hijacked” the issue and used Golden Rice as a springboard to rail against all GM crops. Largely due to this controversy, along with political and technological obstacles, nearly 10 years after it was unveiled, Golden Rice has yet to make its wide debut in the paddies of the developing (and vitamin A–deficient) world. “Once [the science] is there, your initial belief is that your work is done, but by far it is not,” says Beyer.
But Beyer, Potrykus, and several collaborators have continued to forge on, refining the technology that made Golden Rice possible and amassing a larger consortium to try to get the enhanced staple crop into the dinner bowls of the people who most need it. And the failure of Golden Rice to leap directly into the world’s rice paddies has not dissuaded scientists from trying the same with other enhanced crops: carrots with twice the calcium, tomatoes with 20% more antioxidants, cassava boosted with additional iron, protein, and vitamins. There are dozens of reports in the scientific literature of common food plants that have been engineered to produce increased levels of one nutrient or another. One cannot yet find vast paddies of Golden Rice waving in the tropical sun or fields of super-cassava blanketing African farmland, but this may be about to change.
More than 250 million sub-Saharan Africans rely on the cassava, a starchy tuber native to South and Central America, as their staple food. Cassava supplies 38.6% of the caloric requirements in some parts of Africa, where hunger and nutrient deficiencies grip the populace and more than 40% of global cassava production takes place.
But cassava is not a particularly nutrient-rich food. It lacks much of the iron, zinc, and vitamins A and E that healthy bodies need to grow. University of Nebraska–Lincoln biochemist Ed Cahoon has worked for several years as part of the BioCassava Plus program, which aims to improve the nutritional profile of cassava through genetic engineering.
Launched in July 2005 with $7.5 million from the Bill and Melinda Gates Foundation’s Grand Challenges in Global Health Initiative, the program’s overarching goal is to develop what essentially amounts to a super-charged cassava plant variety—one with increased levels of iron, zinc, protein, vitamins, and resistance to the cassava mosaic and brown streak viruses plaguing African farmers.