The Contradictions of Consumer Genomics

Through numerous conversations I’ve had with scientists, ethicists, and health care providers over the past few years, I’ve picked up on an odd and seemingly contradictory view of consumer genomic testing: it is both meaningless and dangerous. Not to paint a picture of complete professional consensus, as there is none, but from what I hear it’s these two threads that keep intersecting: danger…and irrelevance. To my mind, to be dangerous means to have power or at least be of some import, which implies having some meaning. This leaves me scratching my head and wondering: “Can consumer genetics really be both?” So I’ve been thinking of different scenarios that could explain these seemingly contradictory stances, which I explore below.

Recap of Consumer Genomics

First as a reminder, consumer genomics, or “over the counter genetics,” as I called it in a previous post, refers to companies offering genetic testing direct to the consumer (DTC), versus through a health care provider. These companies may return a range of reports, including on features such as genetic ancestry, who else in the company databases you might be related to, and risk for certain diseases. In addition, and of particular interest to my dissertation research, most DTC companies also offer to customers their “raw” (or un-interpreted) data for download.

You can see several ways both risk and unimportance could stem from these sorts of results. With genetic ancestry, you can learn roughly what proportion of your genome derives from which different geographic populations.

  • Risk: the information is imperfect, because the reference populations are contemporary proxies, not the actual ancestral populations, and not all populations are represented.
  • Irrelevance: people often already have a good sense of this (was I really surprised to learn my genome is 98.2% Northern European?), and even if they didn’t, is it really going to change most people’s conception of their racial, ethnic, and/or cultural identity?

With disease risk it’s hard to generalize given the range of diseases and the relative importance of inherited genetic variation to each one. But let’s focus on common, complex diseases such as type 2 diabetes or heart disease.

  • Risk: people will not understand the limitations of the test results, which are about susceptibility and NOT diagnosis or deterministic prediction, and either over engage in or fail to engage in healthy preventive behaviors or screening tests. Or just generally freak out (“psychosocial distress”).
  • Irrelevance: for many diseases, genetics plays such an infinitesimal role compared to factors in our environments that in the base case (i.e., barring some overwhelming family history) it’s usually pointless to even talk about inherited genetic factors.

Before I get into two scenarios that could explain the meaningless/dangerous tensions, for comedic relief here is one of my favorite XKCD comics on the topic. You can easily see the danger of misinformation and misinterpretation:

webcomic of two people discussing DTC ancestry testing
XKCD web comic,

One should never avoid chocolate without solid evidence.

Scenario 1: Dangerous because it’s meaningless

The first scenario I want to explore is that consumer genomics is dangerous because it’s meaningless. This could be dangerous in two ways. First, it could be just a waste of time and distraction from more important things, especially when it comes to health. Indeed, in the early days of DTC genetics many experts worried that DTC customers would glut the health care system, making unnecessary appointments with their doctors to follow up on meaningless results, sucking up scarce time and resources. Customers (who are also potential patients, in this narrative) think a result is important, take it into their doctor, who in turn doesn’t think it’s important (and maybe rightly so).

And years later there appears to be some merit to that concern, as some studies found that DTC customers did increase the number of screening tests. (For a good review of empirical research on DTC customers and what they do and don’t do, see Roberts and Ostergren, 2013).

A second way meaningless could be dangerous is just the larger issue of people wasting their time and money. This isn’t a problem for the health care system, exactly, but a broader societal issue. Though to this I would argue that there are numerous other areas where we are not particularly protected against misdirected (or misspent) attentions. (I’m looking at you, Netflix!)

Scenario 2: Dangerous because of future meaningfulness

An alternate scenario is that consumer genomics is dangerous because it’s relatively meaningless now but hopefully won’t be in the future. That is, given our current knowledge of how genetic variation contributes to health and disease, there’s not much useful to be learned from the types of tests DTC companies offer. But, as research continues and we get better at integrating genomics with other types of information, the tests may improve. The whole idea of precision medicine is banking on this process getting better.

So there’s a bit of a reputation issue at stake. If people get exposed to genomics through DTC testing, where the results seem dubious and hand wave-y, they may not take it seriously 10 years down the road when their doctor wants to run a whole genome sequencing test on them. If genetics is currently recreational for most people, it may be difficult to recast it in a more serious light in the future. I’m reminded of a comment I heard at a genetics conference a few years ago, surveying the current and future state of the field of genetic research and medicine. The attendee made a comparison to a historical split between astronomy and astrology — at one point in time, everyone was just studying the stars, then the real science split off from the pseudoscience. He posed to the audience: do we (the professional genetics community) want genetics to go the way of astronomy (presumably what real researchers are doing) versus astrology (presumably the speculative activities of consumer genomics)?

It’s an interesting comparison, but also one that highlights the subjectivity of meaningfulness. Some people read their horoscope every day and find it quite meaningful; others would think that a superstitious waste of time. At they very least, I do think we need to keep an eye on the increasing commercialization of genetics and other types of health data, lest the potential gravity and utility of those data for research and medicine become obscured. And, if you do decide to do a DTC test, make sure it’s your spit and not your dog’s that gets sent in. 😉


2 thoughts on “The Contradictions of Consumer Genomics

    1. And check this out:

      The general consensus among sport and exercise genetics researchers is that genetic tests have no role to play in talent identification or the individualised prescription of training to maximise performance. Despite the lack of evidence, recent years have witnessed the rise of an emerging market of direct-to-consumer marketing (DTC) tests that claim to be able to identify children’s athletic talents. Targeted consumers include mainly coaches and parents. There is concern among the scientific community that the current level of knowledge is being misrepresented for commercial purposes. There remains a lack of universally accepted guidelines and legislation for DTC testing in relation to all forms of genetic testing and not just for talent identification. There is concern over the lack of clarity of information over which specific genes or variants are being tested and the almost universal lack of appropriate genetic counselling for the interpretation of the genetic data to consumers. Furthermore independent studies have identified issues relating to quality control by DTC laboratories with different results being reported from samples from the same individual. Consequently, in the current state of knowledge, no child or young athlete should be exposed to DTC genetic testing to define or alter training or for talent identification aimed at selecting gifted children or adolescents. Large scale collaborative projects, may help to develop a stronger scientific foundation on these issues in the future.


      Okay, I know this isn’t about the distinction Sarah highlighted, but you know why I’m posting these.

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