Researchers have identified a gene that could help explain how humans developed spoken language. The gene, known as NOVA1, is unique in humans and appears to influence vocalization patterns.
A study led by scientists at Rockefeller University and Cold Spring Harbor Laboratory in New York found that when the human version of NOVA1 was introduced into mice, their vocalizations changed. While the number of sounds remained the same, their pitch and complexity shifted.
A unique human gene
NOVA1 is found in many species, but humans have a distinct version of it. Most mammals, including primates, share an identical form of this gene, but a small difference appears in the human variant. This minor genetic change may have played a crucial role in speech development.
Researchers believe this gene could be linked to the evolutionary success of early humans. Unlike modern humans, Neanderthals and Denisovans did not have this particular version of NOVA1, suggesting it emerged after the species split from their extinct relatives.
While other genes, such as FOXP2, have also been linked to language, FOXP2 is present in Neanderthals, raising questions about its role in modern human speech.
In contrast, NOVA1 appears to have undergone a more recent evolutionary shift, which may have contributed to advanced communication.
Experimenting with NOVA1 in mice
To better understand the gene’s impact, researchers modified mice to carry the human NOVA1 variant. The results were striking.
Baby mice with the altered gene produced higher-pitched ultrasonic squeaks, possibly as an attempt at increased social interaction, though their calls did not attract more attention from their mothers.
In adult male mice, the gene did not raise pitch but instead added complexity to their courtship vocalizations. The altered mice produced calls with more syllables, suggesting the gene influences communication patterns.
“They ‘talked’ differently to the female mice,” said Robert Darnell, a neuro-oncologist at Rockefeller University. He suggested that even small changes in vocalization could have had a profound impact on human evolution.
A key regulator in brain development
Scientists are still investigating why NOVA1 affects vocalization. They suspect it alters brain development in regions controlling speech, such as the midbrain, brainstem, and cortex.
NOVA1 is known as a “master gene regulator” because it influences more than 90% of human genes. It produces a protein called Nova-1, which helps modify messenger RNA in brain cells. This process changes how neurons make proteins, potentially increasing molecular diversity in the nervous system and shaping speech-related brain functions.
When researchers examined how the human NOVA1 gene affected mice, they found unexpected molecular shifts in RNA processing within brain cells. The changes were especially evident in areas linked to vocal behavior.
“We thought, wow. We did not expect that,” Darnell said. “It was one of those really surprising moments in science.”
A clue to human evolution
Darnell and his team believe this genetic change played a role in the emergence of complex speech. Their research suggests that an early population of modern humans in Africa developed a specific variant of NOVA1 called I197V. This version may have provided an advantage in vocal communication, allowing it to become dominant.
“This population then left Africa and spread across the world,” Darnell said—perhaps using their evolving language skills along the way.
While NOVA1 is just one piece of the genetic puzzle behind human speech, its discovery provides new insights into the evolutionary forces that may have shaped language.
Scientists say further research could uncover more about the gene’s role in brain development and communication, offering a deeper understanding of what makes human speech unique.