Friday, September 27, 2013

The Truth About GMOs

Mama Moses has been growing bananas on her farm in southwestern Uganda for twenty years. She farms only bananas, which is typical of subsistence farmers in Sanga, the impoverished village where she lives. Last year, when she saw the flowers on her banana plants begin to shrivel and yellow bacteria ooze from the cut stems, she knew her crop was doomed. Within months the bacterial infection turned her healthy crop into a black, wilted mess.

Banana Xanthomonas wilt disease (BXW) is one of the greatest threats to banana production in Eastern Africa. Cultural practices provide some control, but they are ineffective during epidemics. More than a thousand kinds of banana can be found worldwide, but none has robust resistance to BXW. Even if resistance were identified, most scientists believe that breeding a new variety using conventional methods would take decades, assuming it is even possible.

BXW creates precisely the sort of food insecurity that affects the world’s poorest people. Bananas and plantains are the fourth most valuable food crop after rice, wheat, and maize. Approximately one-third of the bananas produced globally are grown in sub-Saharan Africa, where bananas provide more than 25 percent of the food energy requirements for more than 100 million people.

For anyone worried about the future of global agriculture, Mama Moses’s story is instructive. The world faces an enormous challenge: with changing diets and population growth of 2–3 billion over the next 40 years, UNESCO predicts that food production will need to rise by 70 percent by 2050. Many pests and diseases cannot, however, be controlled using conventional breeding methods. Moreover, subsistence farmers cannot afford most pesticides, which are often ineffective or harmful to the environment.

Yet many emerging agricultural catastrophes can almost certainly be avoided thanks to a modern form of plant breeding that uses genetic engineering (GE), a process that has led to reduced insecticide use and enhanced productivity of farms large and small.

In spite of these benefits, genetic engineering is anathema to many people. In the United States, we’ve seen attempts to force labeling of genetically modified organisms (GMOs). In much of Europe, farmers are prohibited from growing genetically engineered crops and so must import grain from the United States. And “GMO-free” zones are expanding in Japan.

The strong distrust of GE foods is curious. Opponents typically profess a high degree of concern for human welfare and the environment. They want the same things that scientists, farmers, food security experts, and environmentalists want: ecologically sound food production accessible to a growing global population. But their opposition threatens the great strides that have been made toward these goals through deployment of new technologies.

For 10,000 years, we have altered the genetic makeup of our crops. Conventional approaches are often crude, resulting in new varieties through a combination of trial and error, without knowledge of the precise function of the genes being moved around. Such methods include grafting or mixing genes of distantly related species through forced pollinations, as well as radiation treatments to induce random mutations in seeds. Today virtually everything we eat is produced from seeds that we have genetically altered in one way or another.

Over the last twenty years, scientists and breeders have used GE to create crop varieties that thrive in extreme environments or can withstand attacks by pests and disease. Like the older conventional varieties, GE crops are genetically altered, but in a manner that introduces fewer genetic changes. Genetic engineering can also be used to insert genes from distantly related species, such as bacteria, directly into a plant.

Given that modern genetic engineering is similar to techniques that have served humanity well for thousands of years and that the risks of unintended consequences are similar whether the variety is derived from the processes of GE or conventional gene alteration, it should come as no surprise that the GE crops currently on the market are as safe to eat and safe for the environment as organic or conventional foods. That is the conclusion reached by diverse agricultural and food experts. There is broad consensus on this point among highly regarded science-based organizations in the United States and abroad, including the American Medical Association, the National Academy of Sciences, the World Health Organization, and European Commission Joint Research Centre. In the seventeen years since GE crops were first grown commercially, not a single instance of adverse health or environmental effects has been documented.

by Pamela Ronald, Boston Review |  Read more:
Image: uncredited