What makes human language possible, and how does the same biology contribute to autism?

In a 2026 study published in Science Advances, we traced language ability back to stretches of DNA that changed rapidly just before humans and Neanderthals diverged. These regions, called human ancestor quickly evolved regions (HAQERs), gained binding sites for Forkhead and Homeobox transcription factors, the protein families that include FOXP2, a gene long tied to speech.

We found that genetic variation in these regions predicts spoken language ability today, a result first observed in 350 people and confirmed in over 100,000. The same language-linked variants were more common in Neanderthals, and similar sequences have evolved independently in other mammals that learn their vocalizations.

Why it matters for autism

The study shows how ancient changes in our DNA continue to shape language, with direct relevance to understanding communication differences in autism.

The work builds on the lab's NIH-funded study of the genetics of language impairment, carried out with language researcher Bruce Tomblin and geneticist Jonathan Sebat.

The paper

Casten LG, Koomar T, Thomas TR, Koh J, Hofammann D, Thenuwara S, Momany A, O'Brien M, Murray JC, Tomblin JB, Michaelson JJ. Ancient regulatory evolution shapes individual language abilities in present-day humans. Science Advances, 2026.

Related: our language research and Autism and SPARK. Writing about this study? Contact michaelson-lab@uiowa.edu.