A large international effort in analysing the genome of thousands of people with MS has found many new genes influencing MS development

2011

This study has been in the making for many years. Researchers at the Wellcome Trust and The International Multiple Sclerosis Genetics Consortium have collaborated to map and compare the genome (all or most of the genes of a person) of 9,772 people with MS of European descent with that of control people without the disease. This is done to assess how genetic variations are associated with the development of MS.

Several important findings came out of the study, published in one of the world's most important science journals, Nature. The researchers replicated most of the previously known genetic assocations, but also found another 29 that were not known. The most important findings were:

  • Genes and genetic predisposition did not account for clinical course or severity of disease (importantly, this means that environmental factors are more important than genes once a person has the disease, and we can control many of these environmental influences)
  • There was no evidence of interaction between gender and genetics (that is the female preponderance is mostly due to environmental factors)
  • The stronger the genetic susceptibility, the earlier in life the disease occurs
  • Genes influencing T-cell maturation were over-represented in people with MS, providing compelling evidence that the critical disease mechanisms in MS primarily involve dysfunction of the immune system

The study provides an important blueprint for further MS research, highlighting which factors are worth exploring further.

As reported on the 7.30 Report in response to this paper, genes responsible for vitamin D metabolism were noted in the study, prompting immunologist Professor Graeme Stewart, to say "There is an extremely strong case for a trial of giving people sizeable doses of vitamin D from the time of their first episode of multiple sclerosis".

At OMS we would say the evidence is already so strong that it is only sensible for people with MS to already supplement with vitamin D and not await further clinical trials. And we would go further, and recommend starting vitamin D supplementation immediately for people at risk of getting MS, that is those in places distant from the equator with little sunlight, and relatives of people with MS.

You can read the full study here.


Published December 18, 2012

Douglas Goodin, a neurologist in California, has developed a mathematical model based on known research, that clearly shows the genetic background to the development of MS.

  • He has shown for example, that to develop the disease, one really has to have the genetic susceptibility.
  • However, only a small fraction (less than 2.2%) of the population actually has this genetic susceptibility and can go on to get the disease.
  • Men are more likely to have this susceptibility than women, but if you have the susceptibility, women are more likely to get the disease, around twice as likely. This is due to women being more influenced by environmental factors than men; this also explains why the sex ratio is changing from around 1.6 : 1 women to men, to around 3:1.

The paper goes on to examine the environmental factors known to increase the risk of developing MS for those who have the genetic susceptibility;

  • these are vitamin D level while in utero,
  • vitamin D levels in childhood,
  • infection with the Epstein-Barr Virus (EBV, the glandular fever virus).

While the mathematics is complex, the paper makes very interesting reading. 

genetics
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