Looking at Disease Risk with 23andme

In recent posts, I have discussed the kinds of results you can get by submitting a sample to 23andme.  In this post, I'm going to discuss the one aspect of 23andme that seems to be more troubling than that used to identify ones genealogical heritage.  There is also a health component that can give you some idea of the role that your particular genes play in predicting disease.  Anyone who does this should be aware of a couple of a few facts:

1. This is a new and evolving science.  In many cases genes are clear markers for a given disease, while in others they are not.
2. Often it's not one gene that will predict your chances of eventually developing a disease but a cluster of genes.
3. Genes ARE NOT the total story when it comes to disease.  In many cases, environmental factors can play as large a role if not more of a role in whether or not you will eventually get a disease.
4. Often there are things YOU CAN DO to prevent disease.  
5. For the really sensitive diseases, like Alzheimer's, 23andme gives you the choice of looking at the results or not.

One of the things I like about their service is that you can look at the research on which their predictions were based.  You can see how recent it is, how large the sample size was and their level of confidence on what they are telling you.  Did I have any surprises?  Yes and no.  Here is a graphic for some of the diseases that my genes indicate may put me at an increased risk.

Click to enlarge

According to their results, I am most at risk for coronary heart disease.  This surprised me only because we think of ourselves as a "cancer" family.  My Dad and all four of his siblings developed cancer -- often at a relatively young age.  My mother and her sister did, too.  When I investigated the science behind their prediction, however, I really should have been paying more attention to this one.  I am treated for high blood pressure, common in my family, and I've been diagnosed with supraventricular tachycardia.  Interestingly, both of these conditions are easily treated -- so I can probably avoid what looks like a high risk.

I was NOT at all surprised by the venous thromboembolism prediction.   As I mentioned in an earlier post, I know I have the Factor V Leiden mutation (which they picked up in their testing) that puts me at a higher risk.  The cool thing about knowing, however, is that I doubt I'll ever have this problem.  Any time I've had surgery that puts me at a high risk (knee replacements), I've been treated with blood thinners.  Problem solved.  I also know to avoid certain behaviors (like sitting in one position too long, especially on a long flight).  Movement is essential.

I was really interested in the macular degeneration prediction as this, also, is prevalent in my family.  My opthamologist is aware of my concern and is on the alert for any signs.  So far so good.

I did open my Alzheimer's risk, and even though I have a higher chance of developing this than others in the population, it still is only a one in seven chance.  I'll go with those odds.  What surprised me was how low my genetic predisposition was to ulcerative colitis, since this is a disease I did develop at age 49 and has had a huge impact on my life -- proving once again that genes are only part of the story.

In the next post I'll show you some of the information that is available for each of the diseases.  I'd love to hear your comments on whether or not you would feel comfortable getting results such as these.