Is Myasthenia Gravis Genetic?
Last updated: May 2023
Do your genes play a role in whether you will develop myasthenia gravis (MG)? There are no known risk factors for the disease. But, scientific research continues to shed light on the connection between MG and genetics.
We already know a lot about the origins of MG. Everyone has antibodies – proteins created by our immune systems – to ward off disease. With MG, antibodies turn against you and destroy or act as a barrier to receptor sites on your muscle cells.1
This makes it hard for your nerves to communicate with your muscles using chemicals called neurotransmitters. The result is a drop in nerve signals, which leads to MG-related muscle weakness.1
What is the role of genetics in MG?
Parents do not directly pass MG to their children most of the time. The same is true for other autoimmune illnesses.1,2
In rare cases, women with MG do give birth to babies with the disease, called neonatal MG. These children usually get better if they receive treatment right away. There is another rare form of MG in children. It is called congenital myasthenic syndrome, and it is inherited.1,2
Researchers are looking at the role of your genes in MG. They think genetic factors are partly responsible for its development. They have linked MG to a family of genes called human leukocyte antigens (HLA). These genes manage your immune system. And they help it tell the difference between your own proteins and proteins made by:2,3
- Other intruders
There are different types of HLA, some of which may be connected to MG. Scientists think there is a relationship between:2,4
- Early-onset MG and the genes:
- Non-HLA genes
- Late-onset MG and the genes:
MuSK antibody-positive myasthenia is linked to haplotypes DR14 and DQ5.2. A haplotype is a set of genes that tend to be inherited together.2,4
Researchers are still trying to figure out how gene changes lead to MG.
Genes and autoimmune disease
When a member of your family has an autoimmune disease, your chances of also having it rise, say researchers. Your risk continues to go up the more immediate the relationship. For example, you are more likely to have an autoimmune disease when a parent has it versus a distant cousin.2
But, your overall risk is still not very high. Studies of twins show that when 1 sibling has an autoimmune disease, the other develops it less than half of the time.2
An autoimmune disease like MG may leave you vulnerable to similar illnesses of the immune system. Anywhere from 5 to 10 percent of people living with MG have a second autoimmune disease. These illnesses can form either before or after MG begins. The most common are:2
- Thyroid disease
- Rheumatoid arthritis
My most frustrating MG symptom is _____.