Scientists recently used parts of the human genome to double the brain sizes of Marmoset monkey fetuses.
The study, published in Science Magazine, says they also increased the folds of the monkey brain, which allows a larger brain to fit into a smaller skull. The brain neocortexes, linked to cognition and language control, were also enhanced.
The scientists at The Planck Institute of Molecular Cell Biology and Genetics in Germany and the Central Institute for Experimental Animals in Japan used the human-specific ARHGAP11B gene.
The monkey fetuses were aborted to prevent unintended consequences.