Advertisement

Is Alzheimer's disease hereditary?

Dr. Neal D. Barnard, MD
Psychiatrist (Therapist)

There are genes for Alzheimer's disease that can increase your risk, but there are things you can do - like eating a healthy diet - to lower that risk. Watch Neal Barnard, MD, explain how to test for the gene and what you can do to stay healthy.

 

Dr. Rudy Tanzi, PhD
Neurologist
As scientists reveal more about the genetic causes of Alzheimer's, doctors are using that information to counsel family members of patients with the disease. In this video, Dr. Rudy Tanzi shares his advice for the family members of patients with Alzheimer's.
Dr. Eric Pfeiffer
Psychiatrist (Therapist)

Sometimes caregivers become concerned about the possibility that because someone else in their family has experienced Alzheimer’s disease, they themselves are at greater risk for developing the disease. This concern is for the most part unwarranted.

Advancing age is the greatest risk factor for developing Alzheimer’s disease. For example, at age 65 only one percent of individuals have Alzheimer’s. At age 75 this has risen to ten percent. At age 85, some 35 percent of such individuals have the disease, and at age 90, nearly fifty percent are affected by the disease. Having a single blood relative with Alzheimer’s disease increased the risk for developing the disease only slightly. However, if both parents of an individual have had the disease, the risk for their offspring developing the disease increases substantially.

Hereditary factors do not play a major role in determining whether someone may be at risk for developing Alzheimer’s disease unless two or more blood relatives have had the disease. On the other hand, some 0.5 percent of individuals suffer from a clearly inherited form of Alzheimer’s disease. In these individuals, the disease begins in the person’s forties or fifties, and they generally do not survive much beyond their early sixties. In these individuals, fully one half of all their offspring will inherit the disease.

The Art of Caregiving in Alzheimer's Disease

More About this Book

The Art of Caregiving in Alzheimer's Disease

This is an A to Z Guide to the caregiving experience in Alzheimer's disease. It is easy to read, easy to follow. It is authorative, based on thirty years of experieReconce in caring for Alzheimer's...
Judith London, MD
Psychiatrist (Therapist)

The way that Alzheimer's is inherited, or more accurately, that a person has a higher probability of getting this disease, involves the presence of the APOE4 gene. This gene is related to the APOE series of genes involved in cholesterol processing. Other factors have to be present in addition to APOE4 for Alzheimer's to occur. Many people without this gene still get Alzheimer's.

The good news is that recent studies show that physical exercise can significantly reduce the probability of getting Alzheimer's for those who have the APOE4 gene. Once again, healthy lifestyle practices that are good for the heart are good for the brain.

Betty Long, RN, MHA
Nursing Specialist

It's not likely, but there is a small chance. Familiar Alzheimer’s is a relatively rare inherited form of the disease, affecting less than 10% of the population.

The more common late-onset Alzheimer’s shows no pattern although genetics does seem to play a role. But a family history alone is not enough to cause Alzheimers. Researchers continue to focus on diet, environment and other factors.

Just as a reminder, some of the more common warning signs of Alzheimers Disease are:

  • Difficulty performing familiar tasks or using simple household appliances
  • Disorientation, such as becoming lost on your own street
  • Poor judgment, such as wearing several shirts on a warm day or very little clothing in cold weather
  • Putting items in unusual places, such as a book in the refrigerator, and forgetting how they got there
  • Problems with abstract thinking, such as difficulty in balancing a checkbook
  • Changes in mood or behavior, such as rapidly going from calm to tearful to angry for no apparent reason
  • Loss of initiative, marked by extreme passivity and lack of interest in normal activities

Neurologist and functional medicine expert Dr. David Perlmutter discusses whether or not Alzheimer's disease is hereditary. Watch Dr. Perlmutter's video for important tips and information about the health of your brain.

Alzheimer disease can be inherited; in fact, beyond age, having a family history is the most significant risk factor. New evidence has found that first-degree relatives with Alzheimer disease are 4 to 10 times more likely to develop the disease themselves compared to people with no family history. In other words, if your mother has Alzheimer disease then you have a greater chance of getting the disease compared to someone whose parents do not have it. Regardless of the family history, though, Alzheimer disease presenting before age 60 is quite rare.

Dr. Darria Gillespie, MD
Emergency Medicine Specialist

Even if a close relative has Alzheimer's disease, it doesn't mean you'll contract the disease. Still, if you're worried, here are some tips from Darria Long Gillespie, an emergency room physician, that may help you lower your risk of dementia.

When a family member has Alzheimer's disease, people often wonder about their own chances of developing the disease. Family history is indeed a risk factor for Alzheimer's. If you have a parent or sibling with Alzheimer's, you're more likely to develop the disease than someone who does not have a first-degree relative with this condition. Risk rises further if you have more than one first-degree relative with Alzheimer's. But while heredity is a major factor in a small number of families, for most people, genetics seem to play only a minor role or none at all. As scientists continue to mine new research on genes associated with late-onset Alzheimer's, though, our current understanding may shift.

Genetics is most important in families with a history of early-onset Alzheimer's (occurring before age 50) stretching back for several generations. (The early-onset form accounts for less than 1% of all Alzheimer's cases.) Mutations in three genes are known to cause this type of Alzheimer's: amyloid precursor protein gene (APP), presenilin 1, and presenilin 2. All three genetic mutations increase the production of beta-amyloid, which is deposited in the plaques found in Alzheimer's disease. Excessive amounts of beta-amyloid fragments are thought to be toxic to nerve cells.

If one parent has any of these mutations, each child has a 50% chance of inheriting the mutated form. A child who inherits the mutated gene will inevitably develop early-onset Alzheimer's disease.

Continue Learning about Alzheimer's Disease Causes

Can You Spot the Signs of Early-Onset Alzheimer's?
Can You Spot the Signs of Early-Onset Alzheimer's?
Some 5.7 million Americans—nearly two-thirds of them women—currently live with Alzheimer’s disease, the most common cause of dementia. And we rightly ...
Read More
Does Alzheimer's disease affect people younger than 65?
PhRMAPhRMA
Some 5.1 million people with Alzheimer’s are 65 and older, but an estimated 500,000 people younger t...
More Answers
Who is affected by Alzheimer's disease?
John H. Growdon, MDJohn H. Growdon, MD
The risk of Alzheimer's rises steadily with age. One in eight people ages 65 and older is affect...
More Answers
How Are You Applying Your Down's Syndrome Research to Alzehimer's Disease?
How Are You Applying Your Down's Syndrome Research to Alzehimer's Disease?

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.