Page URL: https://www.bionews.org.uk/page_92319

MS twin study suggests environment plays key role

4 May 2010
Appeared in BioNews 556

Environmental factors, rather than genetics, may play a key role in multiple sclerosis (MS), according to new research published in Nature. The US scientists sequenced the whole genome of one pair of identical twins, only one of the pair who had MS, but failed to find any notable differences, discovering little about the origin of the disease.

Scientists also found no differences in the levels of gene activity when they compared the immune cells of these twins and two other sets of similarly-affected twins.

Researchers had previously identified a handful of gene variants linked to a higher risk of getting MS, and all the twins in the study had at least some of them. 'Both twins came into the world with the same set of high risks for developing MS', said Dr Stephen Kingsmore, a lead geneticist on the study at the National Centre for Genome Resources, US, '....but those genetic factors seem to have been insufficient to cause disease on their own'. The finding 'points to some novel environmental trigger that must be very important to the disease'.

Exactly what environmental factors contribute to causing MS is still unknown. The leading theory is that a virus triggers the immune system reaction that leads to the disease. Smoking and Vitamin D deficiency have also been suggested as possible environmental contributors.

The findings do not mean that genetics plays no role in the disease: the new study is small - it examines only three pairs of twins and one type of immune cell known to be involved in MS. Also, some scientists feel that the analysis was too broad to catch what is likely a 'needle in the haystack' genetic cause of a very complicated disease.

Genes are also known to have some function in the disease - when one identical twin has MS, there is 30 per cent increased risk that the identical sibling will develop it. That compares with an increased risk of only five per cent for a non-identical twin.

 

SOURCES & REFERENCES
DNA comparison of identical twins finds no silver bullet for MS
ScienceNews |  29 April 2010
Environmental factors likely play a role in multiple sclerosis
LA Times |  28 April 2010
First twin sequences: What do they day about disease?
New Scientist |  28 April 2010
Genetic map gives detailed look at MS
San Francisco Chronical |  29 April 2010
Twin study deepens multiple sclerosis mystery
Wired Science |  28 April 2010
Twin study surveys genome for cause of multiple sclerosis
Nature |  28 April 2010
RELATED ARTICLES FROM THE BIONEWS ARCHIVE
1 September 2015 - by Lubna Ahmed 
A recent study by researchers in Canada has found that people who are genetically susceptible to low vitamin-D levels are at a higher risk of multiple sclerosis...
12 December 2011 - by Owen Clark 
A rare genetic variant causing lower levels of vitamin D has been linked to multiple sclerosis (MS), according to scientists...
15 August 2011 - by Dr Rebecca Hill 
Researchers have identified 29 new genetic variants with a link to multiple sclerosis (MS). This brings the total number of genetic changes associated with the disease, which affects around 2.5 million people worldwide, to nearly 50...
6 June 2011 - by Mehmet Fidanboylu 
Researchers have found a link between genetics and the environment that may help to explain the development of multiple sclerosis (MS). The study, published in Nature Communications, identified how vitamin D obtained through diet or sunlight, interacts with certain genes...
4 April 2011 - by Dr Jay Stone 
Scientists from the University of Western Ontario have found that identical twins may not be as identical as we first thought....
6 August 2007 - by Stuart Scott 
After more than three decades of dead-ends and dismay for researchers and Multiple Sclerosis (MS) sufferers alike, two new genes have finally been identified that are thought to be involved in the pathogenesis of MS: the most common neurological disease affecting young adults. Back in 1972, the...
2 October 2006 - by Dr Laura Bell 
UK Researchers have discovered a gene that helps combat multiple sclerosis (MS). The research, published early online in the journal Nature, found that the gene which puts a person at risk of MS, called DR2b, is partnered by another gene, DR2a, which tempers the effects of the...
HAVE YOUR SAY
Log in to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions


Syndicate this story - click here to enquire about using this story.