Human Language Gene Gets Mice Moving

March 7, 2008 -- Scurrying mice would seem to have little to do with human language, but new research has found that a slightly different version of a gene associated with human speech also governs movement in rodents.

The finding gives new meaning to the phrase "loose lips," since the researchers who conducted the study believe that the human ability to speak evolved, in part, from the capacity to move the lips around efficiently.

Scientists first began to zero in on the gene, called Foxp2, when they noticed that people with defects in it had trouble speaking.

"Foxp2 is the only gene thus far to be linked to human speech and language," co-author Simon Fisher explained to Discovery News. "In humans who carry a [defect] in the gene, it leads to them having problems with learning to make rapid sequences of mouth movements."

Fisher is a Royal Society research fellow and head of the Molecular Neuroscience group at the Wellcome Trust Center for Human Genetics at the University of Oxford.

Since Foxp2 in healthy humans is just a mutated form of a gene present in all vertebrates, including rodents, Fisher and his team introduced a defective form of the gene into mouse brains to see what would happen.

While mice with the defective gene appeared to have relatively normal brain structure and development, further testing proved otherwise.

The researchers provided the gene-altered mice with an angled, rotating running track in their cages. Mounted on a greased, steel axle, the track operated like an off-kilter carousel, powered by little mouse legs.