Gene Researchers Have Created Green Mice

These are no Frankenstein mice. Their green feet come courtesy of a fluorescent green jelly fish gene added to their own genome. This allows a team of British scientists to test out gene editing using CRISPR-Cas9 technology.


“We take what were or would have been green embryos and we make them into non-green embryos, so it’s a really great way of demonstrating the method“, said Dr. Anthony Perry, reproductive biologist at the University of Bath.

The technique uses the ribonucleic acid molecule CRISPR together with the Cas9 protein enzyme. CRISPR guides the Cas9 protein to a defective part of a genome where it acts like molecular scissors to cut out a specific part of the DNA. This could revolutionise how we treat diseases with a genetic component, like sickle cell anaemia. The technique is being pioneered in the U.S.
We now have a technology that allows correction of a sequence that would lead to normally functioning cells. And I think you know the opportunities with this are really exciting and really profound. There are many diseases that are have known genetic causes that we now have in principle a way to cure,“explains Jennifer Doudna, Professor of cell biology at the University of Berkeley.
Last year two teams of U.S. based scientists used CRISPR-Cas9 technology in mice to correct the genetic mutation that causes sickle cell disease. Although researchers aren’t yet close to using CRISPR-Cas9 to edit human embryos for implantation into the womb – some are already warning against it.

Dr David King, Director of  Human Genetics Alert, comments: “It will immediately create this new form of what we call consumer eugenics, that’s to say eugenics driven by the free market and consumer preferences in which people choose the cosmetic characteristics and the abilities of their children and try to basically enhance their children to perform better than other people’s children.” Other potential applications of the technology could be to make food crops and livestock animal species disease-resistant. The British team say CRISPR-Cas9 presents a golden opportunity to prevent genetic disease.


The Genome Editor

French biochemist Emmanuelle Charpentier, from the Max Planck Institute in Berlin, was recently awarded the L’oreal-Unesco Prize For Women in Science. The scientist is listed as one of the 100 Most Influential People by Time Magazine. Her discovery, the CRISPR-Cas9, is a gene-editing technology that could revolutionize medical treatments in ways we can only begin to imagine. Marking an incredible leap forward in the long history of genome studies, Emmanuelle Charpentier and her lab partner, scientist Jennifer Doudna, jointly discovered CRISPR-Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats). Behind this name, which sounds like something from a sci-fi novel, is a technology that works like a pair of molecular scissors, allowing to precisely snip the genetic code, letter by letter, along with the programmable enzyme Cas9 able to perform a cut on a double DNA strand. This is a never-before-reached level of precision in genome studies. And one Emmanuelle Charpentier claims could change everyone’s life :

emmanuelle charpentier2

I am excited about the potential of our findings to make a real difference in people’s lives. The discovery demonstrates the relevance of basic research and how it can transform application in bioengineering and biomedicine, said Emmanuelle Charpentier.

While the scientific community agrees that CRISPR-Cas9 is a revolution, the stakes are so high that the question of what’s next seems a difficult one to answer. The technology could be the key to eradicate certain viruses like HIV, haemophilia or Huntington, to screen for cancer genes or to undertake genome engineering. The latter obviously raises moral and ideological issues.

The recent scientific article « CRISPR/Cas9-mediated Gene Editing In Human Tripronuclear Zygotes » published by Protein Cell reports the first experiment on a foetus by a team of scientists in China, and illustrates the potential dangerous consequences (eugenics)  of CRISPR-Cas9 on future generations. Nature & Science refused to publish this experiment, mainly for ethical reasons. This question of ethics reminds us that science and society cannot be isolated from one another.