New here. No family histody of AD, should I still be tested?

[Orangecrush]

Hi! Nice to meet all of you.

Everyone in my family, going back to at least my great great grandparents have lived to be in their late 80's to late 90's and none of them had AD or any other type of dementia. I have an aunt right now who is 96 and still golfs every day. lol My dad just died at 85 from a fall on the stairs in his home. My mom is 85, and is as spry as they come. She can remember every single detail of every single conversation. She facebooks all the time, still does her own hair and makeup, and meets up with the other women in her highschool class, who are still alive. She also goes to church every Sunday. My grandpa, my mom's dad died at 87 of heart failure and he was spry too. He still drove and went out to breakfast every morning with his lifelong friends at a local restaurant, up until he died. I'm not going into every single family member's life-story or cause of death, but my point is everyone in both sides of my family either dies from a fall or basically very old age, and all of them lived at home until they died. They weren't in any need of in-home care of anything.

My siblings are older than me, they're all in their mid to late 60's and they're all fine. So, I feel safe in saying there is no family history of AD. Ive read that usually, if there is an APOE4 gene in the family, that there will generally be a family history of AD, is that true?

Is it likely my family does not have the apoe4 gene? Thank you in advance for your time.

[TheresaB]

I have no family history, I'm a 4/4.

[floramaria]

Is it likely my family does not have the apoe4 gene? Thank you in advance for your time.

Hi Orangecrush
We have a resource on the website that you might want to read through:
Thinking About Testing.

Given your family history, my guess (and it is just a guess, since i am not a genetics expert) is even if there are ApoE4 alleles being passed along, there are probably genetic gifts that are protective. That seems likely given the longevity in your family.
Lifestyle factors is exert powerful influence over genetic expression. And genetics are not the sole driving force behind Alzheimer’s, so following healthy lifestyle is important for everyone who wants to extend physical and cognitive well-being.

You could look at the Primer if you want to learn more. it is written by a physician member and discusses the importance of sleep, dietary choices, exercise, stress reduction and other factors that are beneficial for everyone, as well as others that are specific to reduction of ApoE4- associated risks.

[NF52]

Hi! Nice to meet all of you.
...I feel safe in saying there is no family history of AD. Ive read that usually, if there is an APOE4 gene in the family, that there will generally be a family history of AD, is that true?

Is it likely my family does not have the apoe4 gene? Thank you in advance for your time.

Hi Orangecrush,

First, let me tell you how sorry I am that you've recently lost your dad. It sounds like he lived life to the fullest, and I'm sure he was thrilled to have decades with your mom, you and other extended family members. I found that my memories of my dad, who died 33 years ago today, are still vivid and wonderful, and hope you feel that same comfort in the future.

I think you are safe in saying that there's no known family history of diagnosed Alzheimer's disease. That may mean that your family on both sides has some super "resistance" genes, whether or not they have ApoE4. Those unknown genes would have "resisted" the underlying conditions that lead to formation of amyloid plaques and tau tangles that are associated with (but may not directly cause) Alzheimer's, which is the type of dementia for which ApoE 4 is a risk factor.

It's also possible that they had strong "resiliency" genes. Autopsy studies have shown that about 30% or more of people in their 80's and 90's do have Alzheimer's pathology (plaques and/or tangles) but they don't show outward signs of the disease, possibly due to high cognitive reserve that allows them to compensate for mild problems, or high brain structural reserve (like a transportation system with a lot of alternative routes in case of congestion on a main road).

In either case, it makes it more likely that you don't have ApoE 4, but not a sure thing, since scientists have found healthy ApoE 2/4, 3/4 and 4/4 people in their 80's and 90's. And of course people with ApoE 3/3, the most common pattern, can also develop Alzheimer's and other dementias. I think what you can assume though is that you have some great genes to work with, and you can support them by using lots of strategies to minimize your mid-life risks.

Hope you're planning a bucket list that will last through your 90's!