by A new competition for a human ‘language’ can change the way mice squeak when it is included in their DNA.
The gene is called Nova1And in our own species it is remarkably unique. While almost all other mammals have the same Nova1 Variant In their genetic code, a single change of an amino acid is seen in the human version.
This, subtle tweak may have played a crucial role in the origin of spoken language and the expansion and survival of Homo SapiensAccording to researchers of Rockefeller University and the Cold Spring Harbor Laboratory in New York.
Even Neanderthalers and Denisovans do not have the same variant, which means that it must have evolved in the last few hundred thousand years, after our species has earned themselves from these extinct relatives.
Other proposed ‘language genes’, such as Foxp2that also make mice squeak differently are found in the DNA of Neanderthalers. So although they probably also contributed to the origin of human language, they may not be responsible for our more recent evolutionary success.
It is not clear what the language opportunities of our extinct family members were ever, but this recent change has proved to be very successful in the human genome.
In more than 650,000 human DNA sequences, researchers found only six anonymous people who did not have the modern Nova1 variant. Nothing about these individuals is known.
When it comes to the origin of complex human language, Nova1 is “The New Kid on the Block”, Geneticist Wolfgang Enard who at the Foxp2 gene told Carl Zimmer Op The New York Times.
“This gene is part of a major evolutionary change in early modern people and hints to potential old origin of spoken language,” says neuro-oncologist Robert Darnell of Rockefeller University, who has since studied the gene and ties with the disease and intellectual Function since then the early nineties.
“Nova1 Can be a bona fide human language, although it is certainly only one of the many people -specific genetic changes. “
When Darnell and his team generated the human variant of artificially Nova1 In mice they discovered that the rodents squeak differently. Adults and puppies still made the same amount of noise, but their vocalization patterns had changed.
Compared to typical mice, genetically modified puppies made ultrasonic squeaks with higher frequency. Their calls caught the attention of their mother no more than the calls of a check -up, but these sounds can indicate an increased attempt at social interaction, albeit a failed.
Higher frequency calls are also used by adult male mice during dating for similar reasons. When mature male mice were genetically changed with humans Nova1 Variant, their squeaking during the courtship were not higher like the puppies. Instead, their vocalizations include more complex syllables.
“They spoke otherwise against the female mice,” explains Darnell. “One can imagine how such changes in vocalization can have a major influence on evolution.”
Why the mice sound different with humans Nova1 Variant is a mystery that Darnell and his colleagues would like to solve. The team suspects that the human variant of molecular shifts causes in some parts of the developing rodent brain – whether they are the vocal paths of the middle brain and brain stem or more recently developed areas in the Cortex, which regulate pitch and frequency.
The Nova1 Gene is known as a ‘Master Gene Regulator‘Because it influences more than 90 percent of other human genes during development.
Nova1 Codes a protein called Nova-1 That can cut out and rearrange that sections of Messenger RNA If it binds to neurons. This changes how brain cells synthesize protein, probably create molecular diversity In the central nervous system.
When Darnell and his team ‘Humanized’ mice with the Nova1 Variant they found molecular changes in the RNA split that was seen in brain cells, especially in areas associated with vocal behavior.
“We thought, Wow. We didn’t expect that, “says Darnell.” It was one of those really surprising moments in science. “
For Darnell, understanding Nova1 Has been a career-long effort.
Nova1 It is thought to regulate learning in people, and mutations in this gene can cause serious psychiatric disorders and abnormalities in motor development.
His role in speech development is just starting to arise, and although there is much hypothetical, the possibilities are profound.
“Our data show that an ancestral population of modern people in Africa has developed the human variant I197V, which subsequently became dominant, perhaps because it granted benefits with regard to vocal communication,” Darnell suggests.
“This population then left Africa and spread all over the world.”
Undoubtedly have a chat on the road.
The study was published in Nature communication.
