Amid much debate about the genetically engineering crops across the world, experts have said that sweet potatoes have been found to be genetically modified by nature.

The new research found that nature is making its own set of GM foods and a sweet potato is an example. They said that this process has been happening for thousands of years indicating that the humans have been consuming GM foods for several centuries. The team found a 'foreign DNA' in the vegetable that contains a type of natural genetically modified organism (GMO).

The research study was conducted by scientists from Ghent University in Belgium and the International Potato Institute (CIP). Experts said that earlier researchers have found GMOs but it is the first time that a major crop plant such as sweet potatoes has been found to be modified. The team found that sweet potatoes across the world contain this genetic modification. They were able to find Agrobacterium that is also called as 'nature's genetic engineer' that does 'horizontal gene transfer' involving exchanging genes between different species. The team studied 291 samples of sweet potato from the Americas, Africa, Asia and Oceania, and found evidence of Agrobacterium in all the specimen.

Dr LieveGheysen, one of the researchers, said, "The natural presence of Agrobacterium T-DNA in sweet potato and its stable inheritance during evolution is a beautiful example of the possibility of DNA exchange across species barriers. It demonstrates that genetic modification also happens in nature."