- Down’s syndrome (DS) is a genetic condition that occurs as a result of an extra chromosome called chromosome 21
- Researchers added gene called XIST to human stem cells with DS
- Scientists found this ‘silenced’ the extra copy of chromosome 21
- Breakthrough could lead to gene therapy to treat the condition
American scientists believe they have found a way to ‘switch off’ the extra chromosome that causes Down’s syndrome.
Researchers at the University of Massachusetts Medical School have managed to prevent the condition in human cells in a laboratory.
They believe that this breakthrough could eventually lead to treatments for the syndrome.
Gene therapy has already been used to treat medical problems that result from the presence of one defective gene, but this is the first time that silencing the impact of a whole chromosome has become a possibility.
The BBC reports that the breakthrough means that this could now be possible. However, it will require many more years of research.
A team of scientists at the university added a gene called XIST to lab-grown stem cells with Down’s syndrome.
This gene is important in natural cell development as it turns off one of the two X chromosomes that are found in female embryos.
The researchers found that it could be used in the same way to silence the extra copy of chromosome 21 that is found in people with Down’s syndrome.
Lead researchers, Dr Jeanne Lawrence, told BBC News: ‘The research means that we have a new way – right away – to study the cellular basis for Down’s Syndrome, that could help identify drugs for Down’s Syndrome.
Researchers have managed to prevent the condition in human cells in a laboratory
‘At the same time we have made it conceivable – not necessarily possible or effective, that still needs to be proven – but conceivable, that you could use just a single gene to correct the over-expression of the whole chromosome. So it makes genetic therapy for Down’s syndrome more conceivable where it really wasn’t before.’
Carol Boys, chief executive of the Down’s Syndrome Association, told BBC News: ‘The findings could have serious implications for future work that may be of real benefit to people with Down’s Syndrome.’
Down’s Syndrome is a genetic condition that causes learning disabilities and a characteristic range of physical features.
It occurs as a result of an extra chromosome called chromosome 21.
The degree of learning disability varies between people with the syndrome.
People with Down’s Syndrome are often shorter than average, have eyes that slant upwards, small ears, and reduced muscle tone.
They are also prone to heart defects, thyroid problems, infections, blood disorders and early onset Alzheimer’s disease.
Down’s Syndrome is one of the most common genetic causes of learning disabilities and about 750 babies are born with the condition every year in the UK.
By EMMA INNES
Thank you dailymail.co.uk