A team of researchers led by an Indian American scientist has genetically engineered toxin-free cottonseeds, potentially unlocking a large source of nutrition.
Cotton fibre continues to be a globally vital textile crop. The leftover cottonseeds are a high source of protein, but the presence of the toxic chemical gossypol makes them unfit for human consumption.
To remove gossypol from cottonseeds, Keerti Rathore and colleagues from the Institute for Plant Genomics and Biotechnology, A&M University, Texas used RNA interference to disrupt a key gene for synthesizing gossypol in developing seeds, according to an article publishing online this week in the proceedings of the US National Academy of Sciences.
The technique produced mature seeds with gossypol levels well below the safe level for human consumption. Gossypol levels remained high in other parts of the cotton plant, however, allowing the seeds to maintain their natural, chemical defences.
Considering that the 44 million metric tons of cottonseed produced annually could nutritionally support 500 million people, gossypol-free cotton may provide a boon for global malnutrition, the researchers say.
Also, besides the potential of edible cottonseed, RNA interference could possibly be applied to other crops with toxic components, such as fava beans, to increase their utilization.
Co-authors include Ganesan Sunilkumar, LeAnne M Campbell, Lorraine Puckhaber, and Robert D Stipanovic.