There are a number of concerns about safety of using genetically modified plants. One of the major issues is a vague concern that using GMOs may cause bringing genes from distantly related organisms into plants. But an international team of biologists has reported the rather remarkable observation that this kind of gene transferring has occurred naturally in a major crop plant: the sweet potato.
Agrobacterium rhizogenes and Agrobacterium tumefaciens are plant pathogenic bacteria capable of transferring DNA fragments bearing functional genes into the host plant genome. This naturally occurring mechanism has been adapted by plant biotechnologists to develop genetically modified crops.
Among 291 tested accessions of cultivated sweet potato, all contain one or more transfer DNA (T-DNA) sequences. These sequences, which are shown to be expressed in a cultivated sweet potato clone suggest that an Agrobacterium infection occurred in evolutionary times. One of the T-DNAs is apparently present in all cultivated sweet potato clones, but not in the crop’s closely related wild relatives, suggesting the T-DNA provided a trait or traits that were selected for during domestication.
The researchers, rather optimistically, come to a conclusion that their finding, that widely and traditionally consumed sweet potato plants are naturally transgenic, could affect the current consumer distrust of the safety of transgenic food crops.
Source: PNAS
Via: Ars Technica