This web page was produced as an assignment for Genetics 677, an undergraduate course at UW-Madison.
Popular Press Review: Science Daily
Review & Opinion
In March of 2008, Science Daily, a popular press archive with the latest in science news, released a story on the most recent research on the role of the GRIK2 gene and its GluR6 subunit in bipolar disorder (BPD), published in the journal of Molecular Psychiatry. This study was groundbreaking in that it was the first to develop an appropriate animal model system for research into BPD. The lack of such a system was a major obstacle to further research progress. A model system such as the one developed here would help researchers to better understand BPD and to test new pharmaceutical treatments for later development in humans. Furthermore, until this research study the role of the GluR6 receptor in regulating the extreme mood swings of BPD was unknown.
The rationale for the study was based on the recent link of the GluR6 receptor to emergent suicidal ideation, a dysphoric state, with individuals given antidepressants. Research has shown that kainate receptors such as GluR6 respond to the neurotransmitter glutamate, and that many mood disorders are correlated with defective glutamatergic systems. Because those afflicted with bipolar disorder are more susceptible to antidepressant-induced dysphoric states, the authors set out to investigate the possible connection between the GluR6 receptor and bipolar disorder.
The researchers’ approach was to genetically engineer mice of several different strains to have a defect in the GluR6 subunit of the GRIK2 gene, one of the kainate receptors associated with BPD. These genetically engineered mice were compared to control mice throughout the study. The engineered and control mice were given tests designed to approximate the symptoms of mania associated with BPD, and observations were made on their behavior. In addition, the mice were treated with lithium, a common mood stabilizer successfully used in humans diagnosed with BPD, to observe whether the engineered mice also exhibit a positive response.
The results of the tests showed that the engineered mice exhibited many symptoms characteristic of a manic mood state. Some of the observations included generally increased activity levels, a heightened response to amphetamine (which indicates hyperactivity in mice) as well as increased risk-taking behavior and aggressiveness. Treatment of the engineered mice with lithium reduced the hyperactive, aggressive, and risk-taking behavior observed in the mice during the various tests.
This short popular press article does an excellent job emphasizing the rationale behind the research study, the importance of their novel animal model system, and the implications for the discovery of potential pharmaceutical treatments for humans with BPD. Exposition of methods was lacking, however, and it was not described how the successful genetic engineering of the defective-GluR6 mice was performed or confirmed. In addition, the researchers’ names and laboratories are not cited in the text, although the original publication is cited.
References:
1. Molecular Psychiatry (2008, March 13). Bipolar Disorder: Manic Mouse Made With One Gene Missing. ScienceDaily. Retrieved February 12 2009, from http://www.sciencedaily.com/releases/2008/03/080312081256.htm
2. Picture retrieved from http://wwwimage.cbsnews.com/images/2003/11/01/image581314x.jpg
Ashley Bateman, [email protected], last updated 5/13/09
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