Researchers have released the most detailed map of the human brain to date, giving scientists — and interested laypeople — the opportunity to explore the brain’s genetic makeup from the comfort of their computer desk.

The Human Brain Atlas, a $55 million project developed by the Allen Institute for Brain Science, maps the anatomy, nerve structure, cell features and gene activity of the adult human brain. It is the first resource to link brain areas — approximately 1,000 of them — to their underlying genes, says Allen Jones, PhD, the institute’s CEO.

“For the first time, researchers will be able to locate all the areas of the human brain in which a gene is active, or alternatively, all of the genes that are active in a particular area of the brain,” Jones says.

Such information can help scientists connect the symptoms of a neurological disorder with the disease’s biochemistry, and to create better-targeted and safer drugs.

The human brain atlas follows several other free online atlases released by the institute, including a comprehensive mouse brain finished in 2006 and an atlas of the mouse spinal cord.

Allen institute scientists are also working with other researchers on National Institutes of Health-funded projects to develop genetic maps of the brain at different developmental stages, in both humans and macaque monkeys. Those atlases are also available on the institute’s website.

The Allen Institute is not the only place developing computerized resources for brain science. Also in the works, but not yet available to the public, is the five-year, $39.5 million NIH-funded Human Connectome project, which aims to map how the brain is “wired” — how different areas of the brain connect and coordinate with one another.

Researchers at Washington University and the University of Minnesota will gather neuroimaging data from 1,200 healthy young adults, as well as extensive behavioral and genetic information. 

“Scientists know a lot about brain genetics and chemistry and about brain connectivity in animals, but this project will add an entire new class of data to human neuroscience that we expect will transform our understanding of the human brain,” says National Institute of Mental Health Associate Director Michael Huerta, PhD, who directs the effort. (To find out more, visit Human Connectome.)

Already, researchers are using the new brain mapping tools to aid their work on specific diseases and disorders. For example, the University of Pennsylvania’s Maja Bucan, PhD, studies the genetic basis of autism spectrum disorders. She says that she’s found the data on the developing brain particularly useful.

Genetic studies of children with autism have in some cases identified mutations and small chromosomal rearrangements in genes known to be involved in brain development. By letting her team examine the patterns of many genes during different stages of early brain development, the atlases have allowed her to look at the dramatic changes these genes undergo in different brain regions at different times. 

“These databases allow you to be much more creative,” Bucan says. “Instead of focusing on a specific gene, they let us study whole sets of related interacting genes that are expressed in the same neuronal tissue.”

Those spearheading the atlases hope the maps will make it easier for scientists to share and pool data, which in turn may inspire more rapid discoveries about diseases and their treatments.

“Increasingly, these kinds of projects are getting the whole neuroscience community on the same page,” Huerta says.

—T. DeAngelis