Scientists may be a lot closer to understanding and hopefully treating speech impediments like stuttering or stammering, thanks to genetically modified mice.
None other than King George VI has made it obvious that stuttering, a communication disorder characterized by interruptions in fluency through prolongations or repetitions, is a challenge mentally and socially. However, it is also not commonly understood until a mutated gene called Gnptab has been discovered.
Now the researchers are putting the genes to the test by working with genetically modified (GM) mice pups that are between 3 and 8 days old. The animal model makes a perfect choice since mice, especially the babies, are known for creating different complex sounds.
To properly assess the sounds produced, the researchers also developed algorithms that can help measure pauses and vocalizations, as well as allow them to listen to these sounds as mice can produce pitches that can no longer be heard by human ears.
The test didn't make the mice stammer per se, but "this is a huge first step towards an animal model of stuttering," said Terra Barnes, one of the authors of the study.
The data from 3.5-minute recording sessions revealed that the mice pups exhibited abnormal sound patterns that may be comparable to a human stutter such as longer pauses in between vocalizations. Further, GM mice seemed to speak in less-random syllables than their non-GM counterparts, which may then be likened to repetitions of words during stammering.
The research is published online April 14 in Current Biology.
What makes the results even more incredible for the researchers is the fact that the mutated gene is also responsible for getting rid of dirty molecules in cells. However, given the huge role of such gene, they didn't notice any other defect on the mice other than the speech patterns.
"One of the things we find scientifically interesting about stuttering is that it is so precisely limited to speech. It's a very clean defect in an incredibly complex task," said associate professor Tim Holy, PhD, and the study's lead author.
Nevertheless, to produce the correct speech rhythm requires just the right amount of control of the oral muscles and breathing.
There's no cure for stuttering yet, although there are already many different types of therapies available to improve speech. The study may expand the understanding on the genetic component of the condition that will hopefully lead the way to a more precise treatment for at least 1 percent of the world's population.
