*The picture in the header was taken from here.
This web page was produced as an assignment for Genetics 677, an undergraduate course at UW-Madison.
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Organism Phenotypes
Defects in the human UBE3A gene lead to Angelman Syndrome. Experiments have been done on model organisms such as mouse, zebra fish, fruit fly and worms to see how defects in the homologous UBE3A gene in these organisms affect them respectively. Typically, RNA interference (RNAi) is performed to knock out the homologous UBE3A gene in each organism. Since this gene is conserved across these organisms, the phenotypes expressed by them will give scientists insights into how this gene works and how defects in it give rise to this disorder.
Several organism-specific databases such as MGI (mouse), WormBase (worm), FlyBase (fruit fly), and ZFIN (zebra fish) were used to identify the phenotypes caused by the knock out of the homologous UBE3A gene.
Mus musculus (mouse)
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abnormal spatial learning
abnormal posture hypoactivity
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The listed phenotypes in each column were taken from 2 different experiments. The one on the left was taken from an RNAi experiment done by Arthur L Beaudet while the one on the right was taken from an experiment by Joseph Wagstaff. For more details of the experiment on the left, click here. For the one on the right, click here.
Caenorhabditis elegans (Worm)
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Drosophila Melanogaster (Fruit Fly)
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Danio rerio (zebrafish)
Unfortunately, ZFIN did not return any result for RNAi experiment done on zebra fish. This suggests that there could be little or no such experiments that are carried out on zebra fish.
Unfortunately, ZFIN did not return any result for RNAi experiment done on zebra fish. This suggests that there could be little or no such experiments that are carried out on zebra fish.
Analysis
The phenotypes displayed by the organisms which were missing functional copies of the UBE3A gene were mostly consistent with the symptoms of Angelman syndrome patients. These phenotypes include impaired learning, movement difficulties, seizures, abnormal cerebral cortex and dendrite morphology and sleeping disorders. Among the four organisms, mouse displayed phenotypes that are closest to those of AS patients. This is probably because mouse is a mammal and is phylogenetically the closest to human.
Besides being easy to handle and taken care of, mouse displays close similarity in phenotypes of AS patients. This suggests that mouse is a valuable model organism in the research of Angelman syndrome and explains why researchers are more keen to use mice in their research,
The phenotypes displayed by the organisms which were missing functional copies of the UBE3A gene were mostly consistent with the symptoms of Angelman syndrome patients. These phenotypes include impaired learning, movement difficulties, seizures, abnormal cerebral cortex and dendrite morphology and sleeping disorders. Among the four organisms, mouse displayed phenotypes that are closest to those of AS patients. This is probably because mouse is a mammal and is phylogenetically the closest to human.
Besides being easy to handle and taken care of, mouse displays close similarity in phenotypes of AS patients. This suggests that mouse is a valuable model organism in the research of Angelman syndrome and explains why researchers are more keen to use mice in their research,
If you find my website helpful, please consider donating to the Foundation for Angelman Syndrome Therapeutics (FAST)
Created by Jonathan Mok
[email protected]
Last updated 02/23/2012
Genetics 677
Created by Jonathan Mok
[email protected]
Last updated 02/23/2012
Genetics 677