In every cell of our bodies, there are tiny coils of DNA, the blueprint that makes us who we are. Our genes, made of DNA, influence everything from our eye color to our height. They also play a role in our likelihood of developing certain medical conditions, including dementia.
Most dementia cases aren’t directly inherited like some other diseases. Instead, certain genes can increase your risk, but they don’t guarantee you’ll develop dementia.
There are also rare forms of dementia, like familial Alzheimer’s disease, that are directly passed down through families. But these are less common. Let’s dive deeper into the different types of dementia and how genes can affect your risk.
Genes and Their Role in Dementia
Genes are the basic building blocks of heredity. They contain the instructions for all the traits that make us who we are, from our eye color and height to our susceptibility to certain diseases. We inherit our genes from our parents, receiving half from our mother and half from our father.
Sometimes, changes or errors occur in our genes, known as mutations. These mutations can be inherited from our parents or occur spontaneously. Most mutations are harmless, but some can increase the risk of developing certain health conditions, including dementia.
When it comes to dementia, most of the identified genes are considered risk factors, meaning they increase the likelihood of developing the condition, but they don’t guarantee it. One of the most well-known risk genes for Alzheimer’s disease (AD), the most common type of dementia, is the APOE-e4 gene.
But having a risk gene doesn’t mean you will definitely develop dementia.
Many people with risk genes never experience any symptoms, while others without them do. The relationship between genes and dementia is complex and involves a combination of genetic, lifestyle, and environmental factors.
Genetics of Alzheimer’s Disease
AD is the most common type of dementia in the United States, affecting nearly 7 million Americans. While most cases are not directly inherited, genes play a significant role in influencing a person’s risk of developing the disease.
Risk Genes vs. Deterministic Genes
Think of your genes like a recipe for your body. Most genes linked to AD are like adding a pinch of extra salt to the recipe – they increase the likelihood of developing the disease, but they don’t guarantee it. These are called risk genes.
On the other hand, some rare genes are like replacing a key ingredient with something completely different – they directly cause Alzheimer’s to develop. These are called deterministic genes. If you inherit one of these, you will develop Alzheimer’s, usually at a younger age than the more common forms of the disease.
APOE-e4 Gene
One of the most well-known risk genes for AD is called APOE-e4. Everyone inherits two copies of the APOE gene, one from each parent. Having one copy of APOE-e4 increases your risk of developing Alzheimer’s, and having two copies increases the risk even more.
But not everyone with this gene variant develops the disease, and some people without it do.
Familial Alzheimer’s Disease (FAD)
Familial Alzheimer’s disease (FAD) is a rare type of Alzheimer’s caused by deterministic genes. It’s passed down from parents to children, and people with these genes will inevitably develop the disease, usually in their 40s or 50s.
Other Forms of Dementia
While Alzheimer’s disease is the most prevalent form of dementia, other types can also have genetic links, particularly in their rarer forms.
Frontotemporal Dementia (FTD)
Frontotemporal dementia (FTD) is a group of brain disorders that cause changes in behavior, personality, and language. These changes happen due to damage in the frontal and temporal lobes of the brain. FTD often appears earlier in life than Alzheimer’s disease, typically affecting individuals in their 50s and 60s.
About 40% of FTD cases have a family history of the disease, suggesting a genetic link. For these individuals, there is a 50% chance that the condition was inherited from a parent. Researchers have identified several gene mutations that may play a role in familial FTD, but the exact causes of both inherited and sporadic FTD remain unknown.
CADASIL
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare, inherited form of vascular dementia. It’s caused by mutations (changes) in the NOTCH3 gene. This gene provides instructions for making a protein that’s important for the health of small blood vessels in the brain.
Familial Lewy Body Dementia
Lewy body dementia (LBD) is a type of dementia that causes changes in thinking, memory, and movement. People with LBD may experience confusion that comes and goes, see things that aren’t there, and have difficulty with balance and walking. While most cases of LBD happen for unknown reasons, a small number are caused by a specific gene change passed down through families.
Familial Creutzfeldt-Jakob Disease (CJD)
Creutzfeldt-Jakob disease (CJD) is a rare and aggressive type of dementia that progresses quickly. Most cases happen by chance, but about 10-15% of CJD cases run in families.
This familial CJD is caused by a change in a gene called PRNP. This gene is responsible for making a protein in the brain. If a parent has this faulty gene, there’s a 50/50 chance they will pass it on to each of their children, who could then develop CJD.
Huntington’s Disease
Huntington’s disease is a brain disorder that gets worse over time and affects movement, thinking, and emotions. Unlike other types of dementia, Huntington’s is caused by inheriting a single faulty gene. If a parent has Huntington’s, each of their children has a 50/50 chance of also inheriting the gene and developing the disease.
When to Talk to Your Doctor About Dementia
While genetics can play a role in dementia risk, it’s important to remember that many factors contribute to this complex condition. If you’re concerned about yourself or a family member, don’t hesitate to talk to your doctor.
Early Signs and Symptoms
Recognizing the early signs of dementia is crucial for timely intervention. Common early indicators include:
- Forgetting recently learned information or important dates and events
- Difficulty completing familiar tasks, following a plan, or working with numbers
- Confusion with time or place
- Struggling with everyday activities like cooking, paying bills, or following conversations
- Increased anxiety, depression, agitation, or uncharacteristic behavior
Genetic Testing
If you’re concerned about dementia, consult your primary care physician. They can perform initial assessments and refer you to specialists like neurologists or geriatricians if needed.
While genetic testing for dementia is available, it’s not routinely recommended for everyone. It’s most useful for individuals with a strong family history of early-onset dementia or certain rare genetic forms. If you’re considering genetic testing, talk to your doctor or a genetic counselor to discuss the benefits and limitations.
Early intervention is key to managing dementia effectively. If you have any concerns, don’t hesitate to seek guidance from a healthcare professional.
Nurturing Well-Being at 12 Oaks Senior Living
At 12 Oaks Senior Living, we understand that dementia is a journey, not a destination. Our memory care communities are designed to provide a safe, supportive, and engaging environment for individuals living with Alzheimer’s and other forms of dementia.
Our specialized care programs are tailored to meet the unique needs of each resident. We offer personalized assistance with daily activities, medication management, and 24/7 support from our compassionate and trained staff. We believe in the power of connection and create opportunities for social interaction, meaningful activities, and continued learning.
Our goal is to help each resident maintain their independence and dignity while enjoying a fulfilling and active lifestyle. We understand that families play a vital role in the well-being of their loved ones, so we encourage active participation and provide resources and support along the way.
If you’re seeking a memory care community that prioritizes individualized care, engagement, and overall well-being, we invite you to explore 12 Oaks Senior Living.
We’re here to help you and your family navigate this journey with compassion and expertise.