Would You Want to Know If You're at Risk for Alzheimer’s?

Would You Want to Know If You’ll Get Alzheimer’s?

Meryl Comer:  We’re in a world of genomics.  James Watson who co-discovered the double-helix structure of DNA had his genome mapped and was only the second to have done it.  The cost has come down considerably.  I think it was a million dollars to have it done when he had it done. But he told Big Think that the one and only thing he didn’t want to know was his risk for Alzheimer’s.  Now do you think he made the right choice?

Dr. Troncoso:  I think the team might have not found anything.  The question is do you want to know whether you are high risk for Alzheimer’s disease.  I think it is a very personal decision.  Some people may not want to do it.  Others who are very practical for planning reasons may want to do it, but with the understanding that unless it is in one of these families, the 3%, you know.  In the rest of the population there is not a single marker that can tell you for sure they will have Alzheimer’s disease, even the most important one APOE you can have APOE4 alleles and you can still escape the disease. So it may be important for some people.  They want to plan their life, yeah, why not? But if you don’t want to do it I won’t blame you.

Meryl Comer: In terms of full disclosure about whether or not you want to know if you can’t treat for a disease like Alzheimer’s: I had the test.  I wanted to know for life planning.  Did you want to know?  Do you know?

Dr. Guarente:  No, my feeling is I would like to know about risk for any disease that can be treated, but for a disease for which there is really no treatment I would rather not know.

Dr. Arancio:  I don’t know and I don’t think it is important, partially for the same reason that he has said.  And the second thing he has said, what if I find out before I have two copies of APOE4?  I also know that doesn’t mean that I have developed necessarily disease and what if I know that I am the good apple and not the [...] or the [...]?  It does not mean that I have not developed the disease.

Dr. Troncoso:  I haven’t had a full genetic screening, but I do know my APOE, just at serendipity we needed blood when we started doing it in the lab.  I gave a sample and that is what I know and it’s okay, but I don’t have you know.  I didn’t do it because I wanted to know whether I would get Alzheimer’s disease.  Even if I knew that I have the E4 allele, that doesn’t mean high risk, but there is no certainty. 

Meryl Comer: Dr. Gandy?

Dr. Gandy:  I don’t know.  I tend to plan for the worst anyway, so planning I think I'm going to cover anyway.  I think the issue is whether one is ready to deal with that information psychologically, and I've never felt that I really wanted to have that thing sort of hanging around.

Dr. Troncoso:  There is one more twist to this.  It has to do with your children, so the question is if for some reason you’re going to have a child and you may want to know whether you have a gene that will increase the risk in them.  That would be the other situation which I would think about it.

Recorded on October 29, 2010

Genetic testing is advancing rapidly, and we can now find out our risk factor for developing Alzheimer’s. But without a cure or treatment available, what’s the point?

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