"Scientists at the Seattle-based Allen Institute for Brain Science—backed by Microsoft MSFT +1.85% co-founder Paul Allen—have spent more than a decade building an intricate map of the human brain. Today they announced the latest major discoveries from that effort, and even they were surprised by what they found. Despite the complex structure of the brain and the 20,000 genes in the human genome, brain activity is not all that diverse. Yes it’s true, no matter how much you gripe about how different you are from, say, your annoying boss, your brains really work quite similarly.
Using data from the Allen Human Brain Atlas, the scientists investigated gene “expression,” or usage, across different regions of six human brains. Because of the diversity of the genome and the brain’s intricate architecture, they thought they would find hundreds of thousands of gene-expression patterns, but they found just 32. “This was rather surprising. The number of combinatorial possibilities for these genes should be enormous,” says Michael Hawrylycz, an investigator at the institute. “But what we find is that these patterns are very stereotyped, in the sense that almost all genes look like one of these 32.”"