DAS-68416-4

DAS-68416-4 is a genetically engineered soybean that has had its DNA modified to withstand broadleaf herbicides in the phenoxy auxin group (such as the herbicide 2,4-D) and the herbicide glufosinate. Its manufacturer, Dow AgroSciences LLC, petitioned the USDA in November 2010 to deregulate (legalize) it. 2,4-D Soybeans are highly controversial as 2,4-D was one of the chemicals (along with 2,4,5-T) in Agent Orange.

2010: Dow Petitions U.S. to Deregulate DAS-68416-4
On November 17, 2010, the USDA Animal and Plant Health Inspection Service received a petition from Dow AgroSciences requesting the deregulation of DAS-68416-4. The petition describes the soybean as follows:


 * "DAS-68416-4 soybean is a transgenic soybean product that provides tolerance to the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and glufosinate. This herbicide-tolerant soybean will provide growers with greater flexibility in selection of herbicides for the improved control of economically important weeds; allow an increased application window for effective weed control; and provide an effective weed resistance management solution to the increased incidence of glyphosate resistant weeds.


 * "DAS-68416-4 soybean plants have been genetically modified to express the aryloxyalkanoate dioxygenase-12 (AAD-12) and phosphinothricin acetyltransferase (PAT) proteins. The AAD-12 protein is an enzyme with an alpha ketoglutarate-dependent dioxygenase activity which results in metabolic inactivation of the herbicides of the aryloxyalkanoate family. The aad-12 gene, which expresses the AAD-12 protein, was derived from Delftia acidovorans, a gram-negative soil bacterium. The PAT enzyme acetylates the primary amino group of phosphinothricin rendering it inactive. The pat gene expressing the PAT protein was derived from Streptomyces viridochromogenes.


 * "The aad-12 and pat genes were introduced into DAS-68416-4 soybean using Agrobacterium-mediated transformation. Molecular characterization by Southern analyses of the DAS-68416-4 event confirmed that a single, intact insert of the aad-12 and pat genes were stably integrated into the soybean genome. A single copy of each of the genetic elements of the aad-12 expression cassette is present and the integrity of the inserted DNA fragment was demonstrated in three different breeding generations, confirming the stability during traditional breeding procedures. Southern analyses also confirmed the absence of unwanted DNA such as the plasmid backbone DNA in DAS-68416-4 soybean. Segregation data for breeding generations confirmed the predicted inheritance of the aad-12 and pat genes."

On July 13, 2012, APHIS published a notice in the Federal Register, alerting the public that Dow's petition as well as APHIS' plant pest risk assessment and draft environmental assessment were available for public review and comment. Public comments were due on or before September 11, 2012.

Related SourceWatch articles

 * Herbicide Tolerant Crops
 * Dow AgroSciences
 * Biotechnology
 * 2,4-D
 * Biotech Riders in the 2012 Farm Bill
 * Glufosinate

External resources

 * Petition for Deregulation of Dow2,4-D and Glufosinate Tolerant Soybean, Dow AgroSciences.
 * Draft Plant Pest Risk Assessment, USDA.
 * Draft Environmental Asessment, USDA.