In 1996 gene flow was discovered to be much more common that previously thought. According to Science magazine, many ecologists say it is only a matter of time before an engineered gene makes the leap to a weedy species, this creating a new weed or invigorating an old one. A public health disaster was narrowly averted in 1996 when a group of researchers tried to improve soybeans by giving them a gene from the Brazil nut. The gene from the Brazil nut was successfully transferred to soybeans. After this had been accomplished, but before the soybeans were sold commercially, independent researchers tested the soybeans to see if it would cause allergic reactions in people.
Many people are allergic to nuts, particularly Brazil nuts.
In some people, allergic reaction to Brazil nuts is swift and fatal. A series of laboratory tests on humans confirmed that the genetically modified soybeans did provoke Brazil-nut allergy in humans. They could not feed the genetically modified soybeans to people for fear of killing them, but through scratch tests on skin, they confirmed unequivocally that people allergic to Brazil nuts were allergic to the modified soybeans. In discussing their findings in the New England Journal Of Medicine , the researchers pointed out that tests on laboratory animals will not necessarily discover allergic reactions to genetically modified organisms. Only tests on humans will suffice.