- Flavr Savr
The Flavr Savr
tomato was the first commercially grown genetically engineered food to be granted a license for human consumption. It was produced by theCalifornia n companyCalgene , and submitted to the U.S.Food and Drug Administration (FDA) in1992 . It was first sold in1994 , and was only available for a few years before production ceased. Calgene made history but mounting costs prevented it from becoming profitable, and it was eventually acquired byMonsanto .Characteristics
The tomato was made more resistant to rotting by adding an
antisense gene which interferes with the production of the enzymepolygalacturonase (see "RNA interference "). Unmodified tomatoes are picked before fully ripened and artificially ripened usingethylene gas which acts as a planthormone . Picking the fruit while unripe allows for easier handling and extended shelf-life. Flavr Savr tomatoes could be allowed to ripen on thevine , without compromising their shelf-life. The intended effect was, before all, to slow down the softening of Flavr Savr tomatoes, so that vine-ripe fruits could be harvested like green tomatoes without greater damage to the tomato itself. The Flavr Savr turned out to disappoint researchers in that respect, as the antisensed PG gene had a positive effect on shelf life, but not on the fruit's firmness, so the tomatoes still had to be harvested like any other unmodified vine-ripe tomatoes. [Martineau, Belinda. 2001. "First Fruit: The Creation of the Flavr Savr Tomato and the Birth of Biotech Food". McGraw-Hill.] An improved flavor, later achieved through traditional breeding of Flavr Savr and better tasting varieties, would also contribute to selling Flavr Savr at a premium price at the supermarket.The FDA stated that special labeling for these modified tomatoes was not necessary because they have the essential characteristics of non-modified tomatoes. Specifically, there was no evidence for health risks, and the nutritional content was unchanged.
Fresh Tomatoes
The failure of the Flavr Savr has been attributed to Calgene's inexperience in the business of growing and shipping tomatoes [Charles, Dan. 2001. "Lords of The Harvest". Perseus Publishing.] . The variety of tomato Calgene started with was considered by farmers to be inferior, and insufficient resources were allocated to traditional
plant breeding . As a result, Calgene's fields produced only 25-50% as many boxes per acre compared to most growers. Of these, only half as many as anticipated were large enough to be sold as premium-priced. Furthermore, much of the initial harvest was damaged during processing and shipping because ripe tomatoes are unavoidably more delicate than unripened ones. Equipment designed for handling peaches was purchased, and specialized shipping crates were developed, both at great expense. These costs along with competition from a new conventionally bred Long Shelf Life (LSL) variety prevented the Flavr Savr from becoming profitable, and Calgene was eventually bought byMonsanto which was primarily interested in Calgene's ventures intocotton andoilseed .Tomato Paste
In UK,
Zeneca also produced a tomato paste made from GM tomato that is similar to but often confused with Flavr Savr. The higher pulp content of this GM tomato enables more efficient processing of the thick pastes and ketchups preferred by consumers. The paste was labeled as "genetically altered", and priced (at a loss) below its competitors. This commercialization strategy was primarily intended as amarketing experiment which proved that, at the time, European consumers would accept genetically engineered foods. This attitude was drastically changed after outbreaks ofMad cow disease weakened consumer trust in government regulators Fact|date=June 2007, and protesters rallied against the introduction of Monsanto's Roundup-Ready soybeans. ("seeTrade war over genetically modified food ")Controversies
Addition of an "antibiotic resistance" gene
The Flavr Savr also raised some general safety concerns because of a secondary genetic modification. In order to make it easier to identify plants with the modified gene, the "delayed ripening" modification was supplemented with a
genetic marker , and in this case their chosen marker was a gene segment that confers resistance to a particularantibiotic ,kanamycin . A laboratory demonstration showed that the bacteria can sometimes uptake and incorporateplasmids of genetic material from rotting vegetation suggested the possibility that if Flavr Savr was farmed commercially, it might encourage the emergence of new bacterial strains in the environment resistant to kanamycin. This result did not seem to be known to the experts who advised the FDA.Although kanamycin is not a major antibiotic, there have been concerns that having a genetic resistance to one antibiotic may make it easier for bacteria to evolve resistance to other related antibiotics in the same "family", and since different types of bacteria can sometimes exchange genetic material, this raised questions as to whether it was proper to embed genes into a plant strain for convenience that could conceivably have a negative future impact on public health. Even if the risk of encouraging new super-strains of antibiotic-resistant bacteria was considered "negligible", the idea that a company would choose to implant these "particular" genes into bulk crops, when those genes gave no special advantage either to the product or to the end consumer, raised doubts in some people's minds as to whether the industry was behaving responsibly.
These concerns over antibiotic resistance genes were not generally about the safety of "eating" the resulting tomatoes, but about more general risks associated with the wide scale cultivation of material carrying these genes, and the perception that this gave of the industry's attitude to public safety.
References
External links
* [http://www.soilassociation.org/web/sa/saweb.nsf/b0062cf005bc02c180256a6b003d987f/9f8d26bd0d23b83c8025704600419579?OpenDocument Flavr Savr tomato & GM tomato puree: Problems with the first GM foods]
* [http://www.geo-pie.cornell.edu/crops/tomato.html History of genetically engineered tomatoes]
* [http://www.cfsan.fda.gov/~lrd/bioeme.html FDA policy on "biotech" foods]
* [http://www.soilassociation.org/web/sa/saweb.nsf/848d689047cb466780256a6b00298980/80256cad0046ee0c80256d1f005b0ce5!OpenDocument Flavr Savr tomato & GM tomato puree: The failure of the first GM foods] Article from the Soil Association
* [http://www.accessexcellence.org/RC/AB/BA/Flavr_Savr_Arrives.html The Flavr Savr Arrives] Article from [http://www.accessexcellence.org Access Excellence]
* [http://www.public.iastate.edu/~rhetoric/105H16/cofp/tmrcofp.html "The transgenic tomato"] "Purpose: To show a general reading audience (perhaps readers of a popular science magazine) that genetically engineered crops are needed and safe to consume by discussing the development of a successful genetically engineered crop, the FLAVR SAVR tomato."
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