You, me and the little guy over there with the whiskers have a 99% similarity in our genes including the one to make a tail.

Of the 30,000 genes that we share only 300 are unique to each species making mice the mainstay of medical drug research for decades.  Most of the time a good number of similar genes are silent (thank god– that tail thing could be problematic).  The Allen Institute for Brain Science in Seattle has analyzed the active genes–the ones that send out messages to make functional proteins–verses the dormant ones producing three-dimensional maps of the brains of the two species.  Their results were published in the April issue of Scientific American.

What did they find?

• There are no significant differences in gene expression between the left side of the brain and the right side casting doubt on the popular concept of the creative right verses the literal left.
• It appears that the wiring among the 90 billion neurons in our brains is more important than what is going on within the cells themselves. It is the uniqueness of the circuits that defines the species.

Mapping those circuits is a whole other ball game. Think of trying to untangle a pile of intertwined octopuses. The following video is an excellent representation of the complexity involved.

The supporting structures of the brain, the glia—especially the astrocytes (shown in blue on the previous video)—also appear to play a significant role in cognition as well. Human glia progenitor cells that grow into astrocytes have been injected into the brains of fetal mice.  They developed normally and

produced mice that scored significantly higher on performance tests than their normal counterparts. While this mix or ‘chimera’ form of mouse/human brain may pose ethical questions, it does open the door to what could potentially be a better mouse model on which to study a wide range of human neurological disorders.

OK SciFi types what can you do with all this?

• Animals that can be trained to work for us? Personally I would like to train one of those smart little guys to clean behind my refrigerator.

•  Animal Overlords? Planet of the Mice anyone?  As long as they are generous with the goat-cheese brie I can deal with it.

•  A world where there are no traumatic or degenerative neurological disorders? Now we’re talking.

Let me know where those inventive minds of yours take you.