In Defense of Animal Testing

Annie

Diamond Member
Nov 22, 2003
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and the test was pretty cool too:

http://www.popsci.com/inspired-nature/article/2008-05/treating-blindness-scientists-look-algae

For Treating Blindness, Scientists Look to Algae
Inspired By Nature
Cloning the green goo's factories for producing light-sensitive proteins could lead to more effective treatments for certain types of blindness
By Dan Smith Posted 05.23.2008 at 1:23 pm

What if the key to curing blindness was found in unicellular algae?

In a recent study published in the journal Nature, a group of scientists were able to restore light sensitivity to formerly blind mice using a protein extracted from algaes of the genus Chlamydomonas. The Chlamydomonas are of particular interest because they exhibit phototaxis—an ability to orient themselves toward light sources to aid in photosynthesis. Eager to understand what caused this phenomenon on a genetic level, scientists discovered a sequence of genes that stored the blueprints for generating light-sensitive proteins. A group of researchers at the Friedrich Miescher Institute in Switzerland, headed by Dr. Botond Roska, isolated these genes and introduced them into the eyes of blind mice. What they observed was a dramatic behavioral change that proved the mice had regained their sensitivity to light.

Dr. Roska has a clever analogy for putting his research into perspective: "Imagine giving a speech to a large room of people, but only the first row can hear you," he says. The first row he’s referring to is the eye’s outer layer of rods and cones, the light-sensing cells that line the back of the retina and are the first step in a complex cascade of cells that pass information from the eye to the brain. It’s the job of this first row to pass back what they "hear" to the row behind them. When this first layer of cell is damaged beyond repair from such diseases as macular degeneration or retinitis pigmentosa, the eye becomes blind, even though most of the complex cascading mechanism is still functional. As Dr. Roska describes it, a blind eye is "like a camera with the cap on."

Dr. Roska and his team decided to target the layer of cells below this first layer, injecting the cloned algae genes in an attempt to "turn up the volume of the speech" so that the second row could take up the slack left by a "deaf" first row and pass on the message to the rest of the audience.

To see if the treatment actually worked, two groups of mice, one with sight and one blind, were placed in dark cages for half an hour before the lights were turned on. Once the lights were back, the sighted mice became active and ran around their cage, while the blind mice stayed sedentary. When the mice treated with the Chlamydomonas genes were put through the same test, they exhibited levels of activity almost as high as the sighted mice, suggesting that they could tell the different between light and dark. ...
 

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