That might sound like a silly endeavor, but it's actually a burgeoning field of study called comparative genomics. Researchers all over the world are mapping the genome sequences of the chimp, mouse, rat, fruit fly , nematode worm and at least two types of pufferfish to hold it up to the human genome in an attempt to discover the secrets of evolution and disease. By comparing the genomes of different creatures, researchers can pinpoint which genes have survived hundreds of millions of years of evolution.
Researchers are interested in the mouse because so many biological studies have been done using it.
Because it's a mammal, it is in many ways genetically close to humans. But it's also distant enough that scientists can easily notice similar patterns in gene sequences between mice and humans. These genes, researchers say, are undoubtedly functionally important because they have survived the evolutionary time between mouse and man. Different aspects of biology call for different species to compare with the human, Worley said. Fore example, if a researcher wanted to study the genes or proteins expressed in circulation, it won't do any good to look at very distant species that never evolved a circulatory system.