To many they're vermin, and less salubrious neighbourhoods can be overcome by them. So it might seem strange that scientists would want to clone a rat. But Ralph's creation was a significant achievement.
The Birth of Ralph
Ralph the cloned rat was created by a team of researchers at the National Institute for Agricultural Research in France, working with a biotech company, genOway. Details of their work was published in the journal Science and announced to the world in September 2003.
Ralph was the latest in a long line of animals to be cloned and really came some way after the cloning of other species.
The main reason for this was a huge technical hurdle that was proving difficult to overcome. Rats' eggs start the developmental process almost as soon as they leave the confines of the ovary. That made it extremely difficult to introduce donor genetic material. Eventually researchers were able to stabilise this by chemical means, and the world's first cloned rat was born.
Since that time Ralph has fathered healthy pups, again showing that cloned animals can create normal, healthy offspring. To date there haven't been any reports to the contrary.
As with many cloning attempts in other species, the creation of Ralph was no different; extremely inefficient. 129 cloned embryos were implanted into two females. One became pregnant, giving birth to three male rats, though one of those died shortly after birth. Ralph was the first to be born.
Benefits of Cloning Rats
Scientists claim that cloned rats are essential for medical research into human diseases and disorders. First of all the rat is physiologically very similar to humans, making it an ideal laboratory animal.
Having identical copies of rats is useful because it will enable researchers to tease out the roles genetics and environment play in the development of many diseases. The work can focus on how they respond to different diseases and how their behaviours may change. For example if their genes are identical, any variation in their response may well be due to the environment.
The cloning technology also allows scientists to add, take away or modify genes at will. This will enable them to make laboratory models of diseases such as diabetes and cancer, to see how those disorders progress step by step; and to see how they respond to various therapeutics along the way.