Cheyanne UrsoBIO399 Capstone
Wiki 2 Assignment (Synthesis)
When looking at the effects of genetically modified crops being released into the environment, there are many concerns that become apparent. Genetically modified (GM) crops have become more prevalent in the farming industry. With an increased amount of genetic modification being used, an increased amount of run-off that could be affecting aquatic ecosystems starts to become an issue. By ingesting these GM crops, aquatic organisms could be detrimentally impacted, but does its impact span to future generations down the road? In past research, much has been tested for the impacts on the organism ingesting the GM food, but not following the organism into reproduction and the changes that may be seen in their offspring. I hypothesize that GM crop genes can be transferred to the organism that is consuming it, and therefore passed on to their offspring and future generations based on background research.
Looking at a cellular level, it has been found in a previous study that GMOs have the ability for horizontal gene transfer. (Wiki-Nelson et al. 2011). Since this is the ability to have genetic material transferred between organisms, this is simply a concern of the genetically modified DNA being transferred to the salmon directly. This DNA from their GM diet is absorbed from the food into their bloodstream and then moved to their vital organs (Nielsen et al. 2005). Once this DNA uptake has occurred, the DNA has the ability to replicate and modify other DNA within the salmon.
Once the organ and body systems of the organism have been altered from the genetically modified DNA, the Atlantic salmon would then grow until they are of reproductive age. At this point, vertical gene transfer will occur and the salmon will exchange its DNA, modified by the GM feed or not, with its offspring. If the gene was altered in the adult salmon and passed down to the offspring, then the result will be a change in the organism’s health (Kurland et al., 2003). Changes to organ functions, body size, or fecundity, could all be related to the GM DNA being passed on to the offspring. These issues can have a large impact on the organism and further research needs to be conducted to find out what the extent of damage can be. If, for example, the body size was altered for the second generation, there might be a reduced survival for the smaller salmon resulting in a depletion of that species.
With a decrease in salmon population number, the ecosystem would be limited in its productivity and many other organisms in the region could be impacted as well (Holtgrieve, 2011). This loss of productivity could create a lack of nutrients available to the salmon along with other aquatic organisms inhabiting that area, which would decrease the number of organisms as a whole and change the population dynamics. This result could come full circle by also limiting nutrients in areas where salmon spawn, decreasing the number of eggs that actually hatch and produce healthy adult salmon.
The conclusion that is drawn from the information above is of great importance and needs to be addressed. The potential for genetically modified DNA to be transferred from food to organism, and then from organism to offspring, has the potential to create a detrimental impact on a large scale. Starting with something so small as GM run-off being introduced to the aquatic environment, being passed on to future generations, and turning into the possibility of salmon endangerment.

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References
Holtgrieve, G. W., & Schindler, D. E. (2011). Marine-derived nutrients, bioturbation, and ecosystem metabolism: Reconsidering the role of salmon in streams. Ecology, 92(2), 373-385.
Kurland, C., B. Canback, and Otto Berg. "Horizontal Gene Transfer: A Critical View." Proceedings of the National Academy of Sciences. 5 Aug. 2003. Web. 25 Apr. 2012. http://www.pnas.org/content/100/17/9658.short.
Nielsen, C. R., Berdal, K.G., Bakke-McKellep, A.M. & Holst-Jensen, A. (2005) Deitary DNA in blood and organs of Atlantic salmon (Salmo salar L.). Eur Food Red. Technol., 221, 1-8.
WIKI-NELSEN, C., HOLST-JENSEN, A., BØYDLER, C., & BERDAL, K. G. (2011). Quantification of dietary DNA in tissues of atlantic salmon ( salmo salar L.) fed genetically modified feed ingredients. Aquaculture Nutrition, 17(2), e668-e674. doi:10.1111/j.1365-2095.2010.00817.x