14 DAY TRIAL // Lab rats and mice are the animals that have perhaps advanced medicine and related fields the most, experts believe. Their similarities to us, genetically speaking, have made them the test subjects of choice for a number of experiments investigating various diseases, as well as the action of various individual genes. But engineering them to fit a certain profile is very lengthy, because numerous generations have to be crossbred before a viable specimen is obtained. Now, a company plans to take on the task of supplying the scientific community with rats and mice genetically customized for its needs.
St. Louis, Missouri-based Sigma Advanced Genetic, a division of the chemical reagent company Sigma-Aldrich, is about to start supplying the GM rats this October, officials announce. The animals that it will produce and sell will be lacking specific genes, so as to make it easier for research groups around the world to study the effects of drugs and the effects of diseases under controlled conditions. The custom-made and off-the-shelf knockout rat offer includes, at this point, rodents lacking the ApoE1 gene (useful for investigating atherosclerosis and Alzheimer's disease), as well as the Disc1 gene, which is suspected to play a role in schizophrenia, Nature News reports.
Lexington, Kentucky-based Transposagen Biopharmaceuticals' (TB) founder Eric Ostertag says that the market of lab animals and related services will increase by 12 percent over the next year to three years from now. Right now, the value of the existing markets is estimated to be of around $700 million per year, only a fraction of the overall, multi-billion-dollar market revolving around test animals. TB currently supplies the majority of GM rats being analyzed around the globe.
But, while rodents indeed lead the way in medical research, mice are still the preferred animals. In the UK alone, their numbers outranked those of GM rats by a fraction of 1.2 million to 6,000. The main reason for this discrepancy is the fact that rat genes are much more difficult to manipulate than mouse genes, using nothing more than embryonic stem cells. But this approach to engineering the animals is fairly complex and requires a lot of time and resources.
Sigma-Aldrich plans to use a zinc finger nuclease technology for its GM rats instead. This method relies on engineered fusions of proteins that play a crucial role in DNA binding and cleaving. This approach allows it to delete any gene it chooses directly from a rat embryo, without having to wait for more generations to be born. As the international scientific community already knows, the zinc finger nuclease technology is both very precise and flexible, and its arrival has been highly anticipated.