Mutations in the gene FOXP2 lead to speech and language impairments in humans, but its exact role has not been clear. It turns out that the gene regulates other genes involved in the growth and branching of neuronal projections, making it a key player in neurodevelopment.

Simon Fisher at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his colleagues screened embryonic mouse brain tissue for genes that the FOXP2 protein binds to and teased out 264 targets. These genes cluster in networks that control the formation of neurites, which connect neurons to each other. In mice making defective FOXP2, neurons showed reduced neurite outgrowth and branching.

PLoS Genet. 7, e1002145 (2011)