bit traits that corn does not possess in nature,??? Gengo said in a complaint filed in U.S. District Court in San Francisco.A spokesman for Frito-Lay declined to comment on the lawsuit but said the company stands by the accuracy of its labels.Gengo's lawsuit is one of several dozen making their way through the courts against such brands as General Mills, Pepperidge Farms, PepsiCo, ConAgra and Carg