Genetics and MS
Genetics is the study of our genes and how they might be linked to conditions like MS. We've learned a lot about how genes might influence the risk of developing MS in recent years.
About genetics and MS
What are genes?
Genes are instructions for our bodies, a code passed on from our parents that influences characteristics like our height and hair colour. Each of us has a complete set of around 20,000 genes. We have two copies of each gene, one inherited from each of our parents.
Genes can also affect our chances of developing certain health conditions, including MS. This can happen if the copy of the gene we inherit from our parents is changed slightly. These changes - or mutations - can lead to health conditions. Some conditions are caused by a single small change to one gene. In MS, it's less simple.
Do genes play a role in MS?
Genes do play a role in MS, but they’re only part of the story. There’s no single gene that will definitely cause someone to develop MS, but we know that having certain genes can make a person more susceptible. So far we’ve discovered over 200 genes that are linked to MS.
But most people with these genes won’t develop MS. That’s because environmental and lifestyle factors (like infections, low levels of vitamin D and smoking) also play a role in developing MS. This means that someone who carries some of the risk factor genes still needs to be exposed to environmental factors to trigger the condition.
Researchers are working hard to understand how genes and environmental factors interact to cause MS. We can use this to design strategies that reduce the risk of developing MS.
Can MS be passed on in families?
MS is not passed directly from parents to their children because it is not caused by a single gene. While MS can occur more than once in a family, it’s more likely that this won’t happen.
In the UK, around one person in every 500 currently has MS.
We can work out the chances of relatives developing MS by studying the history of MS in families around the world. The chances of someone with a relative who has MS developing MS themselves is about:
- 1 in 67, if they have one parent who has MS
- 1 in 37, if they have a sibling who has MS
- 1 in 5, if they have an identical twin who has MS
What can we learn from genetics research in MS?
Studying the genes linked to MS can help us to understand why certain people are more likely to develop MS.
We can use this information to design strategies that reduce the risk of developing MS. We can also learn more about how MS develops, by investigating what each gene does. We can use this knowledge to develop new treatments for MS. This type of approach has been successfully used in diabetes, where a potential treatment was developed to target a gene linked to the condition.
Latest genetics research for MS
So far we’ve discovered over 200 genes that are linked to MS. Many of these genes play a role in the immune system, and some have already been linked to other autoimmune conditions like Crohn’s disease and rheumatoid arthritis.
Interestingly, some of the genes have been linked to vitamin D. In 2015, researchers identified four genes that were linked to vitamin D levels. They found that people who carried these genes (and therefore had lower vitamin D levels) were more likely to develop MS.
In 2009, our researches showed that a gene linked to MS can respond to vitamin D. Researchers found that when levels of vitamin D increased, the gene was more active. This ground breaking research could help us understand more about the role vitamin D plays in developing MS.
In 2016 a genetics study revealed a link between body mass index (BMI) and MS. Researchers found that people who are genetically predisposed to having a higher body mass index are more likely to develop MS. This supports previous research that has linked obesity with a higher risk of developing MS.
Our genetics research
We're funding a number of projects to understand how genes play a role in MS:
Predicting who will respond to treatments
Genes might be able to explain why some people with MS respond to treatments, while others don't. We are supporting researchers who are working on ways of identifying and predicting who will respond best to beta-interferon, helping to ensure that people have access to the best treatments for them.
Using genetics to predict progression
As part of our international collaboration, the Progressive MS Alliance, we're funding a number of projects looking at the genetics of MS, including a project in Cambridge investigating why progression of MS occurs in some people but not others.
The genetics of myelin repair
Our researchers in Edinburgh are using a specialised genetic technique to identify genes that promote the formation of myelin and myelin repair. We can use this to develop a new treatments that promote myelin repair for people with MS.