Stammering genes discovered
Jun 06, 2010
STAMMERING has long been recognised to run in families. Studies involving cases in Pakistan, the US and England recently show that stammering affects about 1% of all adults worldwide.
STAMMERING has long been recognised to run in families. Studies involving cases in Pakistan, the US and England recently show that stammering affects about 1% of all adults worldwide. Scientists say they have identified three genes which may cause the problem in some people.
Mutations
They believe that mutations which have already been tied to metabolic disorders may affect the way in which parts of the brain function.
Those affected repeat or prolong sounds, syllables or words, disrupting the normal flow of speech.
Nearly one in 10 of the sufferers examined were found to have a mutation in one of three genes.
Metabolic problems
Two of these have already been linked to two serious metabolic diseases in which components of cells are not effectively recycled.
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.
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.
Physiological
The other cause of stammering is physiological — a symptom that, for whatever reason, the brain’s neural circuits for speech are not being wired normally.
It is only through early intervention that children with persistent stammering have a chance of recovering fluent speech.
BBC
Mutations
They believe that mutations which have already been tied to metabolic disorders may affect the way in which parts of the brain function.
Those affected repeat or prolong sounds, syllables or words, disrupting the normal flow of speech.
Nearly one in 10 of the sufferers examined were found to have a mutation in one of three genes.
Metabolic problems
Two of these have already been linked to two serious metabolic diseases in which components of cells are not effectively recycled.
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.
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.
Physiological
The other cause of stammering is physiological — a symptom that, for whatever reason, the brain’s neural circuits for speech are not being wired normally.
It is only through early intervention that children with persistent stammering have a chance of recovering fluent speech.
BBC