At least 90 percent of the corn and soybeans grown in this country are genetically modified, but genetically modified fish, is turning out to be a much tougher sell.
The latest frontier in the battle over genetically modified food is Atlantic salmon, altered with genetic material from a Chinook salmon and an ocean pout. The result is a fish that grows to market weight twice as fast as wild salmon.
"Most producers will say it takes 24-30 months to produce a market size salmon. We can do that in 18," says Ron Stotish, CEO of Aquabounty. The company created the fish 25 years ago and is waiting for FDA approval.
The salmon would be the first genetically modified meat sold for human consumption. Stotish adds, "this is a generation of technology that can improve productivity, can improve availability of food worldwide."
But opponents of genetically modified food say the fish food could cause allergic reactions - and they're concerned about what would happen if it escapes into the wild.
Michael Hansen, Senior Scientist at Consumers Union says, "that could cause genetic pollution and have an adverse effect on the natural salmon population."
Major grocery chains including Kroger, Safeway, and Whole Foods say they won't carry the salmon even if it is approved.
The FDA has ruled the fish is safe. and said it's unlikely to harm the environment. But the agency stopped short of a final decision and says there's no timeline for when that might happen.