Unless you have a specific health topic in mind, you’ll most likely want to begin by browsing your health results to see what your genetics say about you. Your gateway to all things Health at 23andMe is the Health Overview which highlights some of the interesting results in each of four categories: Disease Risk, Carrier Status (Inherited Conditions), Drug Response, and Traits.
The Health overview doesn’t show all of your results — just a subset that includes the results that are least typical. For example, the Disease Risk category shows three diseases (Type 2 Diabetes, Atrial Fibrillation, and Bipolar Disorder) for which I have higher than average risk, based on genetics alone. Similarly, the Drug Response category shows that my genetics suggest I have increased risk for Esophageal Cancer if I drink alcohol or smoke, that the drug Plavix may not work very well for me, and that I may have increased sensitivity to the drug Warfarin. Since I don’t carry any of the variants tested for the genetic diseases under Carrier Status, that category shows only “Variant Absent” results. The Traits category, however, just shows the first five reports listed alphabetically since results here are not really considered “typical” or “atypical.” (I’ll discuss each of these categories in more detail in future posts.)
You can use the links near the top right of the page to print a summary of your elevated risks and non-typical results or to invite someone to view your health results.
One thing to note about the overview is that it only shows results for “Established Research reports”. Established Research reports are based on published research in which we have the greatest confidence; they use information about associations between genetic variants and disease risk that has strong scientific support (see more about this below).
Each health category also has its own page listing all of the reports in that category and a summary of your results for each. You can click on the category names to reach these more complete listings. The Disease Risk page includes nearly 100 reports related to common or complex diseases and is divided up into those diseases for which your genetics suggests an Elevated Risk, Decreased Risk, or Typical Risk. Given the large number of reports, it can be helpful to focus on the diseases that fall under Elevated Risk, especially if your calculated risk is high or much greater than average.
The main thing to notice within each page is the confidence level, or star rating. Here confidence refers to the the level of scientific support for the general connection between genetics and diseases, rather than confidence in a person’s particular results. Reports with four stars — Established Research reports — use only genetic markers that have been well-established as risk factors in calculating your risk for a disease. 23andMe considers such an association as well-established if multiple large, independent studies have confirmed the finding. (For more detail, see our white paper describing our criteria for vetting genetic associations.) Established Research reports also provide a lot of background information covering the biology of the disease, the balance of genetic and environmental factors, and ideas for monitoring and prevention.
Preliminary Research reports, on the other hand, provide less context and are meant to keep you up to speed on research connecting genetics to a wide variety of conditions. These reports have confidence ratings that are 3 stars or lower, corresponding to the size of the study (studies that included more people with the disease get more stars). Unlike the Established Research reports, Preliminary Research reports give you separate results for each genetic variant linked to a particular disease, rather than combining these results into a single risk estimate. Additional scientific studies may eventually provide enough support to “graduate” some Preliminary Research reports to Established Research status, but until then, those results should be considered purely for informational purposes.
The Disease Risks page summarizes your results for Established Research reports and Preliminary Research reports differently. The summary results for Established Research reports are similar to what you see on the Health overview, with the addition of indicators comparing your calculated, genetics-based risk to the average risk. While Preliminary Research reports don’t calculate an overall risk estimate in this way, they do summarize your risk broadly based on your results for the individual genetic markers. If you only have results that are associated with elevated and typical risk, your summary risk will be classified as elevated. If you only have results that are associated with decreased and typical risk, your summary risk will be classified as decreased. And if you only have typical results or a mix of elevated, decreased, and typical, your summary risk will be classified as typical.
As you’re browsing the page, you might notice that a few of the diseases have multiple reports with different confidence ratings. It is fairly common for a disease to have some established genetic connections but also a number of more preliminary associations that require more scientific support. When there are Established Research and Preliminary Research reports for the same disease, it is helpful to focus more on the Established Research report as these provide more in-depth and reliable information. The Preliminary Research reports, however, do illustrate that genetic research is ongoing, and 23andMe continually updates your Health results as new research comes out.
The pages for Carrier Status, Drug Response, and Traits are similar to the page for Disease Risks — each lists all the reports in that category with a confidence rating and a summary result. They do not include risk estimates, however, because risk estimates are not relevant for those categories.
Once you find an interesting report and click on it, you’ll have much more information at your fingertips. Check out the next post — a guided tour through 23andMe’s 4-star Disease Risk reports!