[LIMA] A study that last year claimed to have found a way to boost the protein content of a staple crop rich in energy but poor in protein has been retracted after researchers failed to find any supporting data to back up its claims.
The study, published in PLoS ONE in January 2011, has been cited at least five times.
The authors claimed to have created a genetically modified (GM) cassava crop that expressed a gene called zeolin, thereby increasing the protein content by 12.5 per cent and potentially allowing the plant to become "capable of supplying inexpensive, plant-based proteins for food, feed and industrial applications".
But the study was retracted this month after the authors were unable to find the zeolin gene in plants from subsequent studies. The retraction notice says that "an institutional investigation revealed that significant amounts of data and supporting documentation that were claimed to be produced by the first author could not be found" and "the validity of the results could not be verified".
Cassava is a staple food in many developing countries, but its nutritional content — especially in protein and micronutrients — is low, something that the researchers from the Laboratory for Tropical Agricultural Biotechnology at the Donald Danforth Plant Science Center in the United States and Mayaguez University in Puerto Rico said they were on the verge of overcoming with the GM cassava.
The lead author of the article, Mohammad Abhary, left the Danforth Center in the middle of 2011, and the corresponding author Claude Fauquetdid not respond to SciDev.Net's requests for comment.
In a statement to Retraction Watch blog, Danforth president James Carrington, admitted that questions arose shortly after the paper was published, when the researchers tried to extend the findings.
Carrington said a more systematic analysis "indicated that the materials published in the paper were not as described, and that the materials that were described could not be found".
Rodomiro Ortiz, professor of plant breeding and biotechnology at the Swedish University of Agricultural Sciences, told SciDev.Net that the case confirms the need not only for rigor in initial research, but for experiments to be repeated before publication.
"It's unfortunate to come to this situation but [retraction] was necessary to keep the ethical values of scientific research," he added.
Ortiz, a breeder of several crops including cassava, had been sceptical when SciDev.Net asked him for an independent comment about this study in 2011, saying that the genetic material of wild and native cassava varieties should be further studied for cassava biofortification, instead of using genetic modification.