You may not expect it, but the mouse and the human genome have a lot in common. The mouse is just one of five other organisms who's genomes are currently under research as well. They are:
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the bacterium, E. coli |
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the fruit fly, Drosophila melanogaster |
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the round worm, Caenorhabditis elegans |
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the yeast, Saccharomyces cerevisiae |
All these organisms' genetic codes are easier to study except for the mouse. The mouse is actually quite closely related to humans as far as the genetic code is concerned. Many mouse and human genes are identical.
This picture will link you to a website that will go much more in depth about the mapping of the mouse genome.
It is because of the similarities that a special emphasis has been put on mapping the human and mouse genome together. Exons and introns might be easily distinguishable after using this technique/approach.
Evolution may also become better understood because for millions of years the common DNA regions between mice and humans have survived. These are referred to as "conserved" regions.
Due to the similarities and despite the differences (i.e. size comparison) the mouse genome will be challenging and difficult to map and sequence, just as the human genome is, because both are complicated and extensive.