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High-resolution maps of genome-wide gene expression have been available for mice for a few years, but only relatively coarse equivalents have been published for the human brain because of the challenges presented by the 1,000-fold increase in size and the limited availability and quality of postmortem tissue. Now Michael Hawrylycz and colleagues at the Allen Institute for Brain Science in Seattle, Washington, have used laser microdissection and microarrays to assess 900 precise subdivisions in brains from two healthy men with 60,000 gene-expression probes. The resulting atlas, freely available at www.brain-map.org, allows comparisons between humans and other animals, and will facilitate studies of human neurological and psychiatric diseases. One early observation from the data is a human-specific pattern — compared with the mouse and rhesus monkey — for the calcium-binding protein CALB1 in the hippocampus. Cover image: Benjamin Facer & Josh Royall/Allen Institute for Brain Science.