10 Misconceptions About GMOs

Genetic Modification of Food Is New
This fresco from the tomb of Menna, from the XVIII dynasty of Amenhotep III (1402-1364 B.C.E.) shows some corn being reaped. Corn has been genetically modified for thousands of years. DeAgostini/Getty Images

Not really. Critics of GMOs often portray genetic tinkering as an unnatural break from farming's pastoral heritage. But in truth, we've messing with the DNA in our food since the dawn of agriculture, by selectively breeding plants and animals with desirable traits [source: Scientific American].

Those plump-kerneled, golden-yellow ears of corn that we love to slather in butter didn't exist 10,000 years ago. Instead, ancient humans took a wild, scraggly grass called teosinte, which has comparatively tiny cobs and kernels, and crossbred the most robust specimens. Modern geneticists who've analyzed the DNA from modern corn and its ancient ancestors found that it took just a small alteration in the genome — about five regions of either single or groups of genes — to change teosinte into the earliest varieties of maize (another word for corn). But minor changes to influential genes can make a huge difference. In genetics, this sort of human intervention in evolution is called artificial selection [source: University of Utah]. Artificial selection over the centuries has increased crop yields and created foods that are bigger, more resistant to pests and disease, and tastier [source: American Museum of Natural History].