Home genetic testing raises more questions than answers

A reader recently wrote:

My [spouse] and I are 63 and childless. We are thinking of spending $99 to get genetic screening on the theory that it could help us plan a little better for our old age. Just as a random example, if I knew my chances for getting Alzheimer’s disease were high, I might want to move into assisted living sooner rather than later. We have many questions. Is this testing accurate? Does it raise more questions than it answers? What are the chances for our information remaining private in a real world where data leaks occur all the time? As a doctor, is this something you would consider for yourself?

Excellent questions.

Here are the answers:

  • Depends what you mean by “accurate”
  • Yes (actually: hell, yes)
  • Iffy
  • No way

Here they are in more detail.

Accuracy of genetic testing

We now have the technical capability of sequencing the entire genome of any given human. This is time-consuming, expensive, and not what commercially available genetic testing does. What they do is test for a panel of specific genes and gene variants. This they do “accurately”. What is still very much in the not-ready-for-prime-time phase is the relationship between those specific genetic variants and the emergence of actual, diagnose-able conditions like Alzheimer’s or diabetes. Even so, finding various genetic variants will never tell you that you will develop a certain disease; the best it can do is give probabilities. And even if those probabilities are high, it still can’t tell you when or how the condition will manifest.

Questions vs answers

Because all you’re going to get is probabilities, you’re always going to have more questions: When is the disease going to show up? How will I know it? Is there anything I can do to prevent or delay its onset? How about minimizing its impact? Again, the relationship between the presence of certain genes (or genetic variants) and specific diseases is far more fuzzy than Marketing will ever admit. The specific site you reference appears to be geared more toward ancestry and family genetics, so I wouldn’t even be sure of the specific utility of any given result, especially in the context of financial planning.

Privacy concerns

In general, my take on Internet privacy is what I call the YouTube rule: yes, anyone can see anything you put up, but because there’s just so much of it, as a practical matter, no one can find anything unless they’re actively looking for it. The other piece of this is that yes, anyone can find out anything they want about you if they really want to, but by and large, unless you’re George Clooney, no one really cares enough to do so. Then again, you may very well run into the problem of insurance companies coming across (or worse, requiring you to provide) the information and then using it against you, either in terms of refusing to issue a policy or affecting your premium. So yes, that’s a very real concern.

Would I spend the money to do this myself?

Absolutely not, and certainly not in the context of financial planning. My take on the current state of commercial genetic testing is that it provides no better medical information than a good family history. Are there situations when it may make some sense? Sure.  Adoptees with no access to medical information about their birth families may find it useful. Exploring one’s genetic heritage? Sounds like fun. But as a financial or estate planning tool? Worse than useless. My advice is to take the $99 and put it towards a good accountant or attorney with experience in end-of-life financial planning who will sit down with you and craft a strategy that makes sense for you.

Lucy Hornstein is a family physician who blogs at Musings of a Dinosaur, and is the author of Declarations of a Dinosaur: 10 Laws I’ve Learned as a Family Doctor.

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