For up to 1 in 10 people with MND, there is evidence of a family history with the disease. However, it is impossible to predict when or if this will cause MND to develop. Other triggers may still be needed for the disease to actually begin. You may hear inherited MND be called familial MND.
Inherited MND is caused by a mistake in the genetic code that holds the instructions for making every protein in our bodies. This mistake is passed down in the family from parent to child. However, it is possible for a person to be a carrier of the gene without ever developing the disease.
A large number of genes that play a part in inherited MND have already been discovered. They can usually be identified through genetic testing, but this is not always conclusive. See the following drop down options on genetic testing and genes that can cause inherited MND.
Although the inherited forms of MND are not as common, it can have a big impact on families affected by them. You can find more information on the issues surrounding inherited MND in our research information sheets:
Where a family history of MND exists, choosing to be tested can be a difficult decision and can affect wider family members, too. For this reason, genetic counselling is recommended, as this provides facts and guidance about options.
If you have MND and want to know more about genetic counselling, ask your neurologist for advice. If someone in your family has been diagnosed and you want to find out more, ask your GP to be referred to a neurologist for guidance. We also provide a research information sheet on genetic testing, which can be found on our research information sheets page.
To date, we know around 70% of the genes known to cause inherited MND. The most common genetic mistakes are:
- C9ORF72, discovered in 2011, which is responsible for around 40 in 100 cases of inherited MND
- SOD1, discovered in 1993, which is responsible for 20 in 100 cases of inherited MND
- TARDBP (TDP-43), discovered in 2008, which is responsible for up to 5 in 100 cases of inherited MND
- FUS, discovered in 2009, which is responsible for up to 5 in 100 cases of inherited MND
Other extremely rare genes that can cause MND have also been found. These discoveries are major breakthroughs, as they can provide important clues as to how motor neurones are damaged in MND. This may advance our understanding of all types of the disease.
To read more news about research articles on genes involved in inherited MND, see our MND Research Blog. There you can find articles on discovery of other genes including NEK1, C21ORF2, TBK1 and TUBA4A.