Author: FM Liew
Date: 09-13-05 01:02
All in the name of humanity...
The mice were created by Tian Xu, a Howard Hughes medical investigator at Yale, and his colleagues at Fudan University in Shanghai, China. To make the mice glow red, they inserted a gene taken from coral and inserted it into the mouse genome. Scientists have done such experiments thousands of times, with a Crayola box of colors and using glowing genes taken from jellyfish and fireflies (see: "Biotech's Glowing Breakthrough").
Glowing mice are old hat--the special thing was the way this batch was created. Xu says his new technique--and cheaper scientific labor in China--could cut the price of creating a new gene modification in a mouse from the $100,000 some pharmaceutical firms pay to a mere $500.
Xu's trick: a genetic quirk called a transposon--a so-called jumping gene--that his team stole from the genome of the cabbage looper moth. Now, he says, the transposon may make it possible to more easily figure out what genes are involved in disease. "We know the Bible," says Xu of the human genome. "Now we want to be able to read and understand it."
Transposons were first discovered more than 50 years ago in corn by a reclusive researcher named Barbara McClintock. An organism's genes--the entire recipe book that explains whether a cell is part of a plant, a moth, a mouse or a person--are written in code on strands of DNA inside the cell called chromosomes. Normally, a gene stays in one spot on the chromosome. But McClintock found that certain genes were vagabonds, moving from place to place--and messing up other genes as they went.
McClintock's jumping genes explain why Indian corn kernels come in so many different colors. The transposons jump from place to place as the kernels reproduce, creating differences in genes for pigmentation. But similar elements were found in fruit flies, allowing scientists to find out what genes do by knocking them out one by one and making the fruit fly the workhorse of modern science.
More details: http://www.forbes.com/2005/09/09/mice-gene-therapies-cx_mh_0912genes_print.html