This article is from the source 'bbc' and was first published or seen on . It will not be checked again for changes.

You can find the current article at its original source at http://news.bbc.co.uk/go/rss/-/1/hi/health/7147742.stm

The article has changed 2 times. There is an RSS feed of changes available.

Version 0 Version 1
Gene therapy 'corrects fragile X' Genetic fix 'corrects fragile X'
(1 day later)
Gene therapy has been used to alleviate symptoms of a condition which is a leading cause of inherited learning difficulties and autism. Genetic engineering has been used to alleviate symptoms of a condition which is a leading cause of inherited learning difficulties and autism.
There is currently no treatment for fragile X syndrome, also linked to epilepsy and abnormal body growth, but the new work raises hopes of progress.There is currently no treatment for fragile X syndrome, also linked to epilepsy and abnormal body growth, but the new work raises hopes of progress.
A Massachusetts team were able to trigger big improvements in mice by tweaking just one gene.A Massachusetts team were able to trigger big improvements in mice by tweaking just one gene.
The results of the study are published in the journal Neuron.The results of the study are published in the journal Neuron.
These findings have major therapeutic implications for fragile X syndrome and autism Dr Mark BearPicower Institute for Learning and MemoryThese findings have major therapeutic implications for fragile X syndrome and autism Dr Mark BearPicower Institute for Learning and Memory
Fragile X is caused by the loss of a gene called FMRP which produces a protein which acts as a brake on protein synthesis in specific areas of brain circuitry.Fragile X is caused by the loss of a gene called FMRP which produces a protein which acts as a brake on protein synthesis in specific areas of brain circuitry.
The theory is that this allows another protein - mGluR5 - which stimulates this process to function unchecked, resulting in over-activity in the brain.The theory is that this allows another protein - mGluR5 - which stimulates this process to function unchecked, resulting in over-activity in the brain.
The researchers, from the Picower Institute for Learning and Memory at Massachusetts Institute of Technology, examined mice which lack the FMRP gene, and show many of the symptoms associated with fragile X.The researchers, from the Picower Institute for Learning and Memory at Massachusetts Institute of Technology, examined mice which lack the FMRP gene, and show many of the symptoms associated with fragile X.
They also created mice that not only lacked FMRP, but also had a 50% reduction in mGluR5.They also created mice that not only lacked FMRP, but also had a 50% reduction in mGluR5.
Fewer abnormalitiesFewer abnormalities
This second group of mice showed fewer symptoms of fragile X, fewer signs of abnormalities in the brain, and fewer signs of abnormal body growth.This second group of mice showed fewer symptoms of fragile X, fewer signs of abnormalities in the brain, and fewer signs of abnormal body growth.
FRAGILE X SYNDROME Boys usually more severely affectedMain problem is mental impairmentOther symptoms include hyperactivity, attention deficit disorder, emotional and behavioural problems, anxiety and mood swingsThere may also be characteristic facial features, such as a long face and large earsOther physical features include flat feet and hyperextensible jointsFRAGILE X SYNDROME Boys usually more severely affectedMain problem is mental impairmentOther symptoms include hyperactivity, attention deficit disorder, emotional and behavioural problems, anxiety and mood swingsThere may also be characteristic facial features, such as a long face and large earsOther physical features include flat feet and hyperextensible joints
For example, loss of the FMRP gene produces overgrowth of connections between nerve cells called dendritic spines.For example, loss of the FMRP gene produces overgrowth of connections between nerve cells called dendritic spines.
However, when coupled with a 50% reduction in mGluR5, spine density was completely normal.However, when coupled with a 50% reduction in mGluR5, spine density was completely normal.
The 'double mutant' mice also showed substantial reduction in epileptic seizures.The 'double mutant' mice also showed substantial reduction in epileptic seizures.
Lead researcher Dr Mark Bear said: "These findings have major therapeutic implications for fragile X syndrome and autism."Lead researcher Dr Mark Bear said: "These findings have major therapeutic implications for fragile X syndrome and autism."
Dr Mark Hirst, scientific adviser to UK Fragile X Society, said: "Whilst we know that many proteins are regulated by the fragile X protein, and are therefore disrupted in fragile X individuals, mGluR5 seems to be one of the most important."Dr Mark Hirst, scientific adviser to UK Fragile X Society, said: "Whilst we know that many proteins are regulated by the fragile X protein, and are therefore disrupted in fragile X individuals, mGluR5 seems to be one of the most important."
However, he stressed that the mice in the study had benefited from reduced levels of mGluR5 throughout their development - something it would be not be able to replicate in a human drug treatment.However, he stressed that the mice in the study had benefited from reduced levels of mGluR5 throughout their development - something it would be not be able to replicate in a human drug treatment.
He added: "We must not take our eye off the other proteins that are mis-regulated, as the basis of fragile X syndrome is likely to be more complex and involve other pathways."He added: "We must not take our eye off the other proteins that are mis-regulated, as the basis of fragile X syndrome is likely to be more complex and involve other pathways."