Is Dementia Hereditary? Exploring The Link Between Genes And Dementia

Most people assume dementia is hereditary based on personal experiences in their own families or people they know.  

But actually, the truth about genes and dementia is a lot more complicated.

In fact, 99 out of 100 dementia cases are not directly caused by genes inherited from parents. 

Certain rare types of dementia are directly caused by genetic changes.

However, most cases happen as a result of a combination of genetic risk factors, lifestyle choices, and other influences. 

Understanding the role genes play – and what we can do to reduce the risk of dementia – is essential. 

Learn more about the link between genes and dementia.

What role do genetics play in our health?  

Genes are the instructions inside your cells that determine how your body grows, develops, and functions.

Made of DNA, they’re fundamental to who you are. You have thousands inside your body, inherited from your parents. They dictate how you look, as well as your chance of inheriting certain diseases, like Alzheimer’s.

There are many different types of dementia which affect different parts of the brain.

However, having a parent or grandparent with dementia doesn’t automatically mean you’ll develop it too – it’s more complex than that and depends on other factors too, like:

• Lifestyle
• Age
• Environment
• Medical history.

Which genes cause increased risk of dementia?

The role of genes in dementia falls into two categories:

Risk genes

Natural variations in our DNA, known as risk genes, can sometimes affect how proteins function, influencing our likelihood of developing diseases like dementia, but they are only one factor.

Faulty genes

In rare instances, a faulty gene inherited from a parent can cause types of dementia like Familial Alzheimer’s Disease, Familial Frontotemporal Dementia, or Familial Vascular Dementia, regardless of other factors. 

It affects around 1 in 100 people, usually leads to early diagnosis, and has a 50% chance of being passed down without skipping generations.

It’s also worth mentioning that for people with Down’s Syndrome, the link between genes and dementia is clearer. 

They carry an additional gene linked to the buildup of amyloid plaques, which is a common trait of Alzheimer’s. This makes someone with Down’s syndrome much more likely to develop dementia – particularly Alzheimer’s.

How can you reduce the risk of dementia?

So, if the majority of dementia cases are a result of various complex factors rather than family history, what can we do to reduce our risk?

While the tips below are great advice for following a healthy lifestyle, improving your brain health, and lowering your risk of dementia, it’s important to be aware they can’t guarantee the prevention of dementia.

Live a healthy lifestyle

Lifestyle factors like nutrition and physical fitness play a role, so stay active and eat a balanced diet.

Sleep!

Good quality sleep is crucial for brain health – chronic sleep problems can increase the risk of dementia.

Be socially active

Mental stimulation can reduce your chance of dementia, so nurture social connections with family and friends. 

Tip: activities like Matching Memories conversation game are a fantastic way to stay connected.

Manage chronic conditions

Properly managing conditions like high blood pressure, diabetes, and high cholesterol can help reduce the risk of vascular dementia.

Reduce stress

High levels of stress can impact your brain function, so practise self care in the form of mindfulness, meditation, yoga, or relaxation exercises to reduce stress and your dementia risk.

See your doctor regularly

Regular check-ups help with early detection and the prevention of cognitive decline, so keep on top of your appointments and don’t shy away from seeking advice and treatment.

Quit smoking and drink responsibly

Research shows smoking and excessive alcohol consumption can negatively affect brain health and increase the risk of dementia.

Can a genetic test tell you if you’ll develop dementia?

Genetic testing can identify faulty genes in cases of familial dementia or detect risk genes like APOE e4 for Alzheimer’s if there’s a strong family history of specific types of dementia or concern about early-onset dementia.

Genetic counselling (which can be available on the NHS via a referral, or can be sought out privately) is recommended to interpret the results.

Genes and dementia: research and advice

Our understanding of genes and dementia is always evolving thanks to scientific advances.

If you’re living with dementia or think you may be at risk of developing it, it’s a good idea to stay informed about the latest research and advice.

For accurate, up-to-date information about genes and dementia, as well as support for people living with dementia themselves or caring for a loved one, we recommending following trusted organisations like:

• Alzheimer’s Research UK
• Dementia UK
• The Alzheimer’s Society