Genomic atlas of the mouse brain revealed

It is a brain map like no other, has been three years in the making, and promises a revolution in neuroscience: a genomic atlas of the mouse brain has been crafted. For neuroscientists, it is as if the genome project has been melded with Google Earth inside the mind of a mouse.

Unveiled in its full glory today, the Allen Brain Atlas contains 85 million images, and enough data to fill 20,000 iPods. The atlas documents the activity of more than 21,000 genes across the entire mouse brain in such fine detail that it is possible pick out individual cells. Already, the atlas has revealed that the mammalian brain contains “hidden” structures, defined by common patterns of gene activity.

“It is a profound enabling tool that is going to dramatically facilitate and accelerate research,” says Marc Tessier-Lavigne, senior vice-president of the biotech firm Genentech in South San Francisco, US, who is also involved with the company that created the atlas. “By having all of the information collated in one place, you can do all of the searching that would not otherwise be possible.”

Ed Lein and colleagues at the Allen Institute for Brain Science in Seattle, US, created the atlas using a technique called "in situ hybridisation". This involves bathing thin slices of brain tissue in chemically labelled RNA probes that bind to sequences, called messenger RNA, produced by individual genes.