GE Plants Spread Genes into Wild Relatives
GE Plants Spread Genes into Wild Relatives: Brassica
Risk
A recent study by Warrick (1) has
confirmed that genetically modified Ready Roundup (RR)
Brassica can escape and outcross with wild
relatives.
The study conducted in Canada with GE
RR Canola (Brassica napus) and the weedy relative Wild
Mustard (Brassica rapa). Scientists reported that the RR
Canola transgene outcrossed readily and persisted in the
weedy mustard relative and was passed on to further
generations. This supports earlier findings in England
that outcrossing is very common in brassica
species.
The findings add to concerns about the
risks of GE brassica being developed and trialled by Crop
and Food Research in New Zealand. Brassica is the name
given to plants belonging to the Cabbage family from
cauliflower, broccoli, to turnips and forage kale.
Brassica are highly promiscuous and readily transfer genes
between plant relatives.
The study was carried out
over 6 years and found that the transgene was stably
integrated into the weedy descendants over that time.
However, the transgenic Brassica plants had reduced male
fertility and reduced pollen viability.
One FI GM
hybrid plant still produced 480 seeds of which 22 carried
the transgene. The plants persisted regardless of Roundup
spraying and fitness costs associated with selection
pressure.
“This transgenic escape into wild weedy
relatives supports concerns that GE brassica are a threat
here," said Claire Bleakley of GE Free (NZ) in food and
environment “Once released out of laboratory containment,
GM pollen will spread to other brassica species both weedy
and food plants, contaminating the environment and food
chain”.
“The worst part of this is the plants
may contain mixtures of GM insecticidal and herbicide
resistant toxins that could affect pollinating insects and
the wider food chain and it will be the farmers, market
gardeners and Councils who will be liable for cleanup and
compensation costs.
GE Free (NZ) in food and
environment believe that ERMA and Crop and Food Research
must look into the new information on the ability of
transgenes to outcross, integrate and survive in the wild
under competitive selection pressure.
There are no
studies on human safety and if levels of toxins cannot be
controlled there may be long term health effects on animals
and people. The research is reason to re-assess their
approval of the Bt GM Brassica
trial.
References:
(1)The case of an
herbicide resistance transgene in a weedy Brassica rapa
population To cite this article: S. I. WARWICK, A. LEGERE,
M.-J. SIMARD, T. JAMES Molecular Ecology 2007 Oct 29 2007;
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-294X.2007.03567.x
Wilkinson
M., Elliott L., Allainguillaume J., Shaw M., Norris C.,
Welters R., Alexander M., Sweet J., and Mason D.
Hybridization Between Brassica napus and B. rapa on a
National Scale in the United Kingdom Science 17 October
2003: Vol. 302. no. 5644, pp. 457 – 459 DOI:
10.1126/science.1088200
http://www.sciencemag.org/cgi/content/short/302/5644/457
Ends