［AP］TRENTON， N.J. - Can animal genes be jammed into plants？ Would tomatoes with catfish genes taste fishy？ Have you ever eaten a genetically modified food？ The answers are： yes， no and almost definitely. But according to a survey， most Americans couldn't answer correctly even though they've been eating genetically modified foods — unlabeled — for nearly a decade.

　　Today， roughly 75 percent of U.S. processed foods — boxed cereals， other grain products， frozen dinners， cooking oils and more — contain some genetically modified， or GM， ingredients， said Stephanie Childs of the Grocery Manufacturers of America.

　　Despite dire warnings about “Frankenfoods，” there have been no reports of illness from these products of biotechnology. Critics note there's no system for reporting allergies or other reactions to GM foods. Genetic modification of crops involves transferring genes from a plant or animal into a plant. Nearly all GM changes so far are to boost yields and deter insects and viruses， cutting the use of pesticides， thus making farming more productive and affordable — a particular aid to developing nations.

　　More than 80 percent of the soy and 40 percent of the corn raised in this country is a GM variety. Global plantings of biotech crops — mostly corn and soybeans and much of it for animal feed — grew to about 200 million acres last year， about two-thirds of it in the United States. Experts say within several years there will be new GM foods with taste and nutrition improvements： cooking oils with less trans fat， tastier potatoes and peanuts that don't trigger allergies.