Han, T. et al. PNAS 116, 17515–17524 (2019)

Human stuttering has been linked to mutations in a number of intracellular trafficking genes, including one called N-acetylglucosamine-1-phosphate transferase subunits α and β—GNPTAB, for short. Mice have a related gene, and while the animals don’t ‘speak’ in the same way as people, Gnptab-mutant pups emit disrupted ultrasonic vocalizations (USV) that researchers from the NIH have found to be similar to human stuttering—essentially, the flow of the pups’ USVs is interrupted by long pauses.

With their stuttering mouse model, the researchers looked more closely at the animals’ brains. They discovered astrocyte deficiencies, particularly in the corpus callosum area. These cells play a variety of roles in maintaining homeostasis in the brain and are thought to contribute to a growing number of neuropathologies. Including now, stuttering.