GM plants use carbon nanofibres

Azonano.com, August 15, 2005

Researchers are developing new techniques that use nanoparticles for smuggling foreign DNA into cells.

For example, at Oak Ridge National Laboratory, the US Department of Energy lab that played a major role in the production of enriched uranium for the Manhattan Project, researchers have hit upon a nano-technique for injecting DNA into millions of cells at once. Millions of carbon nanofibres are grown sticking out of a silicon chip with strands of synthetic DNA attached to the nanofibres. Living cells are then thrown against and pierced by the fibres, injecting the DNA into the cells in the process.

Its like throwing a bunch of baseballs against a bed of nails...We literally throw the cells onto the fibers, and then smash the cells into the chip to further poke the fibers into the cell. - Timothy McKnight, engineer, Oak Ridge Laboratory

Once injected, the synthetic DNA expresses new proteins and new traits. Oak Ridge has entered into collaboration with the Institute of Paper Science and Technology in a project aimed to use this technique for genetic manipulation of loblolly pine, the primary source of pulpwood for the paper industry in the USA.

Unlike existing genetic engineering methods, the technique developed by Oak Ridge scientists does not pass modified traits on to further generations because, in theory, the DNA remains attached to the carbon nanofibre, unable to integrate into the plants own genome. The implication is that it would be possible to reprogram cells for one time only. According to Oak Ridge scientists, this relieves concerns about gene flow associated with genetically modified plants, where genes are transferred between unrelated organisms or are removed or rearranged within a species.

If the new technique enables researchers to selectively switch on or off a key trait such as fertility, will seed corporations use the tiny terminators to prevent farmers from saving and re-using harvested seed - compelling them to return to the commercial seed market every year to obtain the activated genetic trait they need?

This approach also raises a number of safety questions: what if the nanofibres were ingested by wildlife or humans as food? What are the ecological impacts if the nanofibres enter the cells of other organisms and cause them to express new proteins? Where will the nanofibres go when the plant decomposes in the soil?

Carbon nanofibres have been compared to asbestos fibres because they have similar shapes. Initial toxicity studies on some carbon nanofibres have demonstrated inflammation of cells. A study by NASA found inflammation in the lungs to be more severe than in cases of silicosis, though Nobel laureate Richard Smalley, Chairman of Carbon Nanotechnologies Inc. gives little weight to these concerns: We are confident there will prove out to be no health hazards but this [toxicology] work continues.

GM plants use nanofibres