Language gene keeps apes tongue tied

A gene linked to language may be the key to why humans began to master speech 200,000 years ago, researchers say.

The large apes chimpanzees, gorillas and orangutans can communicate using hand gestures and symbols, but our closest animal cousins lack fine-tuned speaking abilities.

Last year, scientists identified the first gene, called FOXP2, that was linked to human language. They found families with a mutated form of the gene had severe language and grammar difficulties.

• FROM OCT. 4, 2001: Genetic link to language discovered

The speech disorder also impaired movement of the mouth, lips and tongue.

Now Svante Paabo and his colleagues at the Max Planck Institute of Evolutionary Anthropology have compared the human version of the gene to its counterpart in mice, chimps, orangutans, gorillas and rhesus macaques.

They found a key change in the gene's sequence seems to affect the ability to articulate by controlling facial movements.

Scientists don't know how the human gene affects language beyond its role in the speech disorder.

Anthropologists say the gene is probably related to the birth of language in humans, but researchers need to know more about the gene's function.

Simply putting the gene in a chimpanzee, for example, wouldn't be enough to make it talk because speech is so complex, Paabo said.

When the researchers compared DNA from humans originating in Africa, Europe, Asia, Australia and New Guinea, they found the language gene became established within the last 200,000 years.

The time frame matches the evolutionary split between modern humans and Neanderthals.

The adoption of the FOXP2 gene supports the theory that the rise of modern humans was driven by the appearance of proficient spoken language, the researchers said.