MS can cause varying levels of disability due to its impact on the nervous system. Symptoms such as mobility issues, fatigue, and cognitive impairment can affect daily life. However, not everyone with MS experiences disability, and many people with the condition may have active lives with the right management. MS can cause varying levels of disability due to its impact on the nervous system. Symptoms such as mobility issues, fatigue, and cognitive impairment can affect daily life. However, not everyone with MS experiences disability, and many people with the condition may have active lives with the right management.

MS is not considered a rare disease, but it is more common in some countries than others. For example, around 1 million people in the United States have MS. People living further from the equator are more at risk, according to epidemiological data. The occurrence of MS has been increasing over time, particularly in women, but the exact reasons for this are not fully understood.MS is not considered a rare disease, but it is more common in some countries than others. For example, around 1 million people in the United States have MS. People living further from the equator are more at risk, according to epidemiological data. The occurrence of MS has been increasing over time, particularly in women, but the exact reasons for this are not fully understood.

The Genetic Links: Is Multiple Sclerosis (MS) Hereditary?

By Rebecca Huxley, BSc, MCSP •

Updated on May 17, 2024

•

Fact checked by Linas Černiauskas, PhD Candidate

The link between Multiple Sclerosis and genetics — Image by Healthnews

Multiple sclerosis (MS) is a neurological disease, meaning it affects your nerves. The exact cause of MS remains a mystery, but genetic factors are thought to play a role.

Is multiple sclerosis hereditary? Here, we’ll explore the role of genetic factors in the development of MS and the likelihood of developing the condition if a close relative is affected. We’ll also look at other factors that may contribute to the onset of this disease.

What is multiple sclerosis?

Multiple sclerosis is an autoimmune disease, meaning your body’s immune system mistakenly attacks healthy cells. In the case of MS, it attacks your neurons.

Your nerves, comprised of connected neurons, control movement, sensation, and many autonomic functions, such as breathing and digestion, throughout your body. Therefore, MS symptoms can vary widely and affect people in different ways. It is not necessarily fatal, but MS can lower your life expectancy.

There is no cure for MS, and it stays with you for life once you develop the condition. However, specialists can recommend MS treatment to help you manage your symptoms.

Symptoms of multiple sclerosis

Common symptoms of MS include:

Decreased balance
Weakness
Fatigue
Problems with walking
Cognitive issues

Bladder, bowel, and sexual problems
Increased muscle tension
Reduced vision and sensation
Nerve pain

Multiple sclerosis is very hard to diagnose and often requires a complex evaluation and testing approach, usually done over various time periods. A neurologist will take into consideration your medical history, perform a neurological examination, order magnetic resonance imaging (MRI) scans of your brain and spinal cord, order specific blood tests, and perform any other investigations needed. This process firstly is designed to rule out other conditions and then to confirm the diagnosis of MS.

Is multiple sclerosis hereditary?

Heredity, or genetics, is responsible for the passing down of traits through families. For example, you may inherit your mom’s hair or your dad’s eye color.

Scientists believe genes play a role in the development of MS, but it is not as simple as inheriting a single specific gene that is responsible for the condition. Instead, it’s more like a genetic predisposition, meaning people with specific genetic traits are more likely to develop MS. Sometimes, the development is associated with exposure to environmental factors.

Current genetic research into MS concludes:

Siblings of a person with MS have a higher risk of developing the condition.
The incidence of MS in children of people with MS is 20–50 times higher than in the general population.
The risk for siblings sharing both parents is 3.11% compared to a risk of 1.89% in siblings sharing one parent in the same family.
Siblings sharing just their mother have a risk of 2.35%, while siblings sharing just their father have a risk of 1.31%.
The twin of a person with MS has a 20–30% chance of developing the condition.

One study investigated a family of three sisters with multiple sclerosis. Parents and grandparents were all tested for MS but had no signs of the disease. The researchers hypothesized that environmental risk factors may have played a role in these sisters’ development of MS.

What causes multiple sclerosis?

While genetic predisposition can increase your risk of developing MS, environmental factors also have an association with the incidence of MS. These include:

Vitamin D deficiency due to the lack of sun exposure
Infection with Epstein-Barr virus (EBV)
Smoking
Adolescent obesity

MS becomes more prevalent in populations living further away from the equator. This is believed to be due to less sunlight exposure and lower levels of ultraviolet light in these countries, meaning people naturally produce less vitamin D in their bodies.

Age and gender also play a role — MS is usually diagnosed between ages 20–40 and is more common in women.

Interestingly, caffeine consumption may decrease your risk of developing MS.

Testing and prevention

Genetic testing is available for MS, but it is not routinely recommended by clinicians. Genetic testing alone cannot accurately predict whether you will develop the condition. The interaction between genes and other factors is complex and not fully understood, so these tests are usually used for scientific and clinical research.

However, there are steps you can take to reduce your risk of developing MS. These include:

Eating a balanced diet
Exercising regularly
Getting enough vitamin D
Avoiding smoking

Family history offers insight into your risk of developing MS. However, the role of genetic factors in MS is not as simple as direct inheritance, and external factors may play a role in the development of the disease.

If you’re concerned about current symptoms or your risk of developing MS, consult a healthcare professional for personalized advice on possible diagnostic strategies and preventative measures. Focusing on healthy lifestyle choices may potentially lower your risk of developing MS while increasing your general well-being.

FAQ

Is MS a disability?

MS can cause varying levels of disability due to its impact on the nervous system. Symptoms such as mobility issues, fatigue, and cognitive impairment can affect daily life. However, not everyone with MS experiences disability, and many people with the condition may have active lives with the right management.

How rare is MS?

MS is not considered a rare disease, but it is more common in some countries than others. For example, around 1 million people in the United States have MS. People living further from the equator are more at risk, according to epidemiological data. The occurrence of MS has been increasing over time, particularly in women, but the exact reasons for this are not fully understood.

Does MS run in families?

Having a family member with MS increases the risk of developing it yourself. However, predicting who will develop the condition is difficult because the exact genetic and environmental factors are not yet fully known. Many people with MS have no close relatives with the disease.

Can you be born with MS?

You can’t be born with MS, but you can be born with a genetic predisposition. The disease is usually diagnosed in people aged 20–40, but rare cases of childhood MS exist. Early-onset MS is diagnosed in people under 18, but this is also uncommon.

Genes play a role in the development of MS, but it is more about genetic predisposition than the inheritance of a single specific gene causing the disease. MS occurs when many genetic and environmental factors come into play.
MS diagnosis is a complex process that requires multiple tests. These include thorough medical evaluations, MRI scans, and neurological evaluation, as well as blood testing to first rule out other conditions and only then confirm MS diagnosis.
While genetic testing for MS exists, it's not standard practice. Instead, focus on lifestyle choices like exercise, getting enough vitamin D, and avoiding smoking to potentially lower MS risk.