Gene clue to what made us different

A gene that may be responsible for the development of speech in humans has been discovered by scientists working for the Max Planck Institute in Leipzig, Germany. The ability to communicate and organise through speech and language is one of the main differences between humans and other animals.

People who inherit certain mutations of the gene in question, which is called FOXP2, have previously been seen to have speech and language difficulties. Now, scientists have looked at the evolutionary development of the gene, and have found that two particular mutations of FOXP2 have been strongly selected for over the last 200,000 years. This corresponds with the time that so-called 'modern' human beings emerged, and suggests that the ability to speak was useful when the survival of the fittest was the order of the day.

The scientists have sequenced versions of the gene in a number of different primates and in mice. They have found that there have only been three changes since the last common ancestor of the human and the mouse, which existed 70 million years ago. There is also a strong suggestion that two of these changes happened since humans diverged from chimps, and the scientists are 95 per cent sure that this occurred between 120,000 and 200,000 years ago.

More work will be required in order to discover exactly what different mutations in the FOXP2 gene mean to different species. Dr Simon Fisher, of Oxford University, said that it is not the only gene connected with language and that others need to be found. He commented that 'making a mouse with the human version of the FOXP2 gene would be easy. But I guarantee you it wouldn't get up and talk'.