December 3, 2012:
Several “brainy” genes that were duplicated in a tiny sea creature nearly 550 million years ago may have led to the massive expansion in intelligence in vertebrate species, two new studies have found.
The studies, published today (Dec. 2) in the journal Nature Neuroscience, suggest this duplication of certain genes spurred an explosion in the number of chemicals that regulate brain function in vertebrates (animals with backbones), thereby leading to greater intelligence, the research suggests.
“This genome event produced a kind of cognitive big bang; it produced a large set of interesting behavior,” said study co-author Seth Grant, a neuroscientist at the University of Cambridge in the United Kingdom. “It produced a molecular toolbox, which in the case of the brain, produced many, many more proteins that you find in the synapses, the junctions between nerve cells.”
The study showed that changes, or mutations, in these genes lead to learning problems in both mice and humans, as well as psychological disorders in humans, said Jeffrey Boore, the CEO of Genome Project Solutions, who was not involved in the study. That supports the notion that these genes “have diversified throughout evolution from their ancient duplications to perform important, specific, diverse roles in mammal cognition in behavior.”