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First language gene discovered
SCIENTISTS think they have found the first of many genes that gave humans speech.
Without it, language and human culture may never have developed.
Key changes to a gene in the last 200,000 years of human evolution appear to be the driving force.
The gene, FOXP2, was the first definitively linked with human language.
A “mistake” in the letters of the DNA code causes a rare disorder in humans marked by severe language and grammar difficulties.
The gene was discovered last year but now scientists have studied the DNA of apes to see what sets us apart from our closest animal cousins.
Mice to men: German and British researchers looked at the chimp, gorilla, orang-utan, rhesus macaque monkey and mouse.
They wanted to see how the gene differed in mice, monkeys and man.
They found slight but crucial changes to the chemical sequence of the gene that happened during the passage of time.
“This is hopefully the first of many language genes to be discovered,” says Wolfgang Enard of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
“It happened in the same time frame when modern humans evolved,” he said.
“It is compatible with the hypothesis that language could have been the decisive event that made human culture possible.”
Genetic roots: Changes to two single letters of the DNA code arose in the last 200,000 years of human evolution. They eventually spread throughout the human population along with our unique capacity for speech.
“The idea is that these changes gave some people an advantage because they were able to communicate more clearly,” says co-author Simon Fisher of the Wellcome Trust Centre for Human Genetics at the University of Oxford, UK.
“This variation in the gene expanded in the population and became fixed so everybody had what is now the human version of the gene.” The possibility that language has genetic roots was first raised in the 1960s.
Scientists argue that there must be a genetic basis to speech and language.
It is universal, complex and acquired almost instinctively by children at a young age.
Hard to digest: The sequence change identified by the German and British team is thought to be linked to an ability to control facial movements — a faculty crucial to language.
John Haught, Professor of Theology at Georgetown University, Washington DC, is not surprised by the finding, reported in the online edition of the journal Nature.
“What may be harder to digest is that such a momentous outcome as language and culture seems to be so exquisitely dependent on a physically infinitesimal genetic difference that allowed for a certain kind of facial movement in our ancestors,” he says.
The researchers stress that other speech and language genes are likely to be discovered.
According to Wolfgang Enard there could be anywhere between 10 and 1,000 such genes.
“We don’t think this is THE speech gene,” Dr Fisher said.
“It influences the ability to speak clearly. The mutation doesn’t remove the capacity for speech completely.”
X-ray vision for doctors
Scientists have been showing off a handheld device that makes the human body seem translucent right in front of your eyes.
The Sonic Flashlight developed by researchers at Carnegie Mellon University in the US combines various technologies to effectively gives the user X-ray vision.
The device looks like a small windowpane attached to a ray gun which produces a live ultrasound scan when placed against a patient’s body.
Researchers say the device could be used to make many surgical and diagnostic procedures such as brain surgery much safer.
Doctors already use ultrasound devices to guide them in performing surgery. But it can be tricky because the doctor has to look away from the patient and into a monitor.
In any case, most of the equipment is expensive and cumbersome.
“When you are guiding procedures, like sticking needles into people, you don’t want to be looking away from your work area,” researcher Damion Shelton said.
“Surgeons and radiologists get very good at hand to eye coordination but we prefer not to have to look away.”
The new device would make such an operation much easier as a doctor would be able to look right at their hands as they work.
Simple to use: The Sonic Flashlight positions an ultrasound scanner and an ultrasound monitor on opposite sides of a see-through mirror.
As you look through the mirror at a patient, the monitor projects the ultrasound image onto the mirror.
The image lines up with the part of the body being viewed.
“We did not invent any of the individual pieces, we invented the combination,” said Mr Shelton.
“Because of the way the display, the mirror and the probe are aligned, you get the perspective of looking at a slice of the person’s body, regardless of where you are standing.”
Mr Shelton believes it the simplicity of the device should appeal to medical experts.
“This does not require any training. Anybody can pick it up and understand intuitively what they are looking at.”
The researchers are now planning to conduct clinical trials of the device and look into other uses for it.
The Sonic Flashlight was recently showcased at the world’s leading computer graphics conference, Siggraph, in the US. — Dawn Sciencedotcom Report
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