How Scientists Transformed Mice Voices by Inserting a Human Language Gene: A Breakthrough in Genetic Research

A newly discovered gene called NOVA1 might change how mice communicate when added to their DNA. This gene is special in humans. Although most mammals have a similar variant, humans have a unique change in a single amino acid.

Researchers from Rockefeller University and Cold Spring Harbor Laboratory believe this small difference has greatly impacted how spoken language began in our species, Homo sapiens. Notably, even Neanderthals and Denisovans lack this specific variant, indicating it developed after our ancestors diverged from these extinct relatives.

While other genes, like FOXP2, are also linked to language and were found in Neanderthals, NOVA1 offers fresh insights. It remains unclear what language capabilities our ancient relatives possessed, but the evidence suggests that the version of NOVA1 found in modern humans has been significant for our success.

Out of over 650,000 human DNA samples, only six individuals did not have the modern version of NOVA1, highlighting its rarity.

Geneticist Wolfgang Enard referred to NOVA1 as “the new kid on the block” when it comes to understanding human language origins. Neuro-oncologist Robert Darnell emphasized that this gene may play a key role in the evolutionary changes that shaped early modern humans and hints at the ancient roots of spoken communication.

When researchers inserted the human variant of NOVA1 into mice, they discovered that the rodents squeaked differently. While both adult and young mice made similar amounts of noise, their vocal patterns changed. The modified pups produced higher-pitched ultrasonic sounds, possibly indicating their interest in social interaction, even if it didn’t catch their mother’s attention.

Adult male mice with the human variant didn’t raise the pitch of their calls during courtship. Instead, their sounds became more complex. Darnell pointed out that these changes in vocalization could significantly affect their evolution.

The reason behind these different sounds in the mice is still a mystery. Darnell’s team is investigating whether the human variant is altering molecular functions in specific areas of the mouse brain that control vocalization.

As a ‘master gene regulator,’ NOVA1 affects over 90 percent of human genes during development. It encodes a protein called Nova-1, which modifies how brain cells synthesize proteins by adjusting sections of messenger RNA. This process likely leads to greater molecular diversity in the nervous system.

When the researchers analyzed the mice that had the human version of NOVA1, they observed changes in the RNA splicing within brain regions tied to vocal behavior. Darnell expressed surprise at these findings, revealing unexpected connections in their research.

Darnell’s journey to understand NOVA1 has been a central focus of his career. This gene might also be crucial for learning and is linked to various psychiatric disorders and motor development issues when mutated.

Research into its role in speech development is just beginning, but the potential implications are vast. Darnell suggested that a group of early modern humans in Africa likely developed the unique variant, leading to its global spread, possibly enhancing their vocal communication skills along the way.

The findings are detailed in a study published in Nature Communications.