Page last updated at 00:01 GMT, Thursday, 11 February 2010

Genes behind stammering uncovered

Mouth
Early intervention can help children overcome stammering

Stammering has long been recognised to run in families, but scientists now say they have identified three genes which may cause the problem in some people.

They believe that mutations which have already been tied to metabolic disorders may also affect the way in which parts of the brain function.

The study involving cases in Pakistan, the US and England appears in the New England Journal of Medicine.

Stammering affects about 1% of all adults worldwide.

Those affected repeat or prolong sounds, syllables or words, disrupting the normal flow of speech.

With early intervention children who stammer can overcome the problem, while for adults therapies are based on reducing anxiety and regulating breathing to improve speech.

But the team from the National Institute on Deafness and Other Communication Disorders (NIDCD) hopes its discovery may pave the way for new treatments.

Nearly one in ten of the sufferers examined were found to have a mutation in one of three genes.

Metabolic problems

Two of these, GNPTAB and GNPTG, have already been linked to two serious metabolic diseases in which components of cells are not effectively recycled.

In addition to finding new forms of treatment, we hope this may help us identifying those children at risk of persistent stammering as it is only through early intervention that they have a chance of recovering fluent speech
British Stammering Association

These disorders, known as lyposomal storage disorders, lead to a build-up of a potentially dangerous substance which can cause problems in almost every area of the body, including the brain.

People with this defective gene need two copies to develop the metabolic disorder, but one copy appears to be associated with stammering.

A third defective gene, which is closely related to the other two, was also found among stammerers but not among the controls.

"For hundreds of years, the cause of stuttering has remained a mystery for researchers and health care professionals alike, not to mention people who stutter and their families," said James Battey, head of the NIDCD.

"This is the first study to pinpoint specific gene mutations as the potential cause of stuttering, and by doing so, might lead to a dramatic expansion in our options for treatment."

The metabolic disorders pinpointed can be treated by injecting a manufactured enzyme into a person's bloodstream to take the place of the enzyme the body fails to produce. It is possible stammering, if confirmed to be caused by the same defect, would respond to the same treatment.

The British Stammering Association welcomed the findings.

"It is just the latest in a string of recent discoveries highlighting the fact that the cause of stammering is physiological - a symptom that, for whatever reason, the brain's neural circuits for speech are not being wired normally," said its director Norbert Lieckfeldt.

FROM BBC WORLD SERVICE

"This puts into sharp relief the bullying and ridicule people who stammer often experience, as opposed to people experiencing, for instance, mobility disabilities.

"In addition to finding new forms of treatment, we hope this may help us identifying those children at risk of persistent stammering as it is only through early intervention that they have a chance of recovering fluent speech."



Print Sponsor


SEE ALSO
Scans spot 'stuttering brains'
01 Aug 02 |  Health
Stammering 'best treated early'
22 Sep 05 |  Health
Blair helps cure stammering
09 Jun 99 |  Health
Stammerers have different brains
23 Jul 01 |  Health

RELATED BBC LINKS

RELATED INTERNET LINKS
The BBC is not responsible for the content of external internet sites

FROM OTHER NEWS SITES
NewsMax.comStuttering Is in the Genes - 2 hrs ago
Mail Online UK Why autistic people often avoid hugs from loved ones - 5 hrs ago
IAfrica.com Stuttering in the genes - 8 hrs ago
CBC Scientists find genes that lead to stuttering; finding could ease parents' guilt - 11 hrs ago
The News International Stuttering linked to defective genes: study - 12 hrs ago
* Requires registration



FEATURES, VIEWS, ANALYSIS
Has China's housing bubble burst?
How the world's oldest clove tree defied an empire
Why Royal Ballet principal Sergei Polunin quit

BBC navigation

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.

Americas Africa Europe Middle East South Asia Asia Pacific