Atlas didn't shrug: mapping the human brain

Emboldened by the success of its mouse brain map, Seattle's Allen Institute for Brain Science announced this week that it is taking on three new, similar "mapping" projects: the human brain, the developing mouse brain, and the mouse spinal cord. Using techniques honed on the mouse brain project, the Allen Institute will catalog the activity of thousands of genes within neural tissues.

Like maps, these "atlases" reveal a whole world of structures that are used as landmarks for scientists studying the brain. A thin slice of brain is first stained and then examined under a microscope. In these atlases, the "landmarks" are fluorescent spots that indicate places where a certain gene has been turned on, allowing the protein it encodes to be made. This technique is useful for understanding the biochemical processes, or "genetic personalities," of different parts of the nervous system, and can be used as a reference when trying to understand what has gone wrong in various neural disorders.

Each Allen Institute project adds a new twist to the atlas business: The human brain atlas will be 2,000 times larger than the original mouse atlas; the developing mouse brain atlas will show how gene activity patterns change over time, from the fetus to adulthood; and the mouse spinal cord atlas is notable because the spinal cord is often overlooked in the scramble to study the brain.

Taking inventory of the active genes in a particular brain or spinal cord region is an enormous, maybe even tedious, endeavor. But the excitement lies in the resulting massive databases that will, like the original mouse brain map, be freely available on the Web. The hope is that sharing this mother lode of data with other scientists will expedite research into neural disorders such as schizophrenia, epilepsy, autism and spinal cord injuries, and help design appropriate drug treatments.

• Michele Solis is a freelance science writer living in Seattle.