Direct-to-consumer (DTC) genetic tests give inaccurate predictions of disease risks and many European geneticists believe that some of them should be banned, the annual conference of the European Society of Human Genetics heard May 31….
Here’s the abstract for the talk which argued that DTC companies don’t give the best disease risk estimates:
Objective: Direct-to-consumer (DTC) companies predict risks of common complex diseases on the basis of genetic markers. Given the low number of markers involved and their small effect sizes, it is unclear whether high-risk groups can be identified. We investigated the risk distributions generated by two DTC companies for 8 diseases.
Methods: We simulated genotype data for 100,000 individuals based on published genotype frequencies. Predicted risks were obtained using the formulas and risk data provided by the companies.
Results: The table presents observed and trimmed ranges of predicted risks. The two companies used different formulas to calculate risks. One company predicted risks higher than 100% for 5 out of 8 diseases, which for AMD concerned 1 in 200 individuals. Observed ranges were smaller for the second company, except for Type 1 Diabetes. Predicted risks higher than 50% were frequently observed for company 1, but were exceptions for company 2. When predicted risks of company 1 were calculated using the formulas of company 2, observed ranges were substantially smaller.
Since I don’t put much stock in the small effect disease risk predictions currently, I am not surprised. But I’d be curious to look at the guts of their results. This was presented at conference, so some caution has to enter into the picture. The main issue I’d always want to emphasize with critiques of the lack of efficacy of DTC is that they need to be evaluated against the baseline of the limits to the efficacy of medical professionals and medicine in general. Genomics and DNA doesn’t make something magical, whether for good or ill.
The second presentation covered in the ScienceDaily release is kind of more disturbing to me. Here’s the abstract:
An increasing number of private companies are now offering direct-to-consumer (DTC) genetic testing services. The tests offered range from tests for single gene, highly penetrant disorders to susceptibility tests for genetic variants associated with common complex diseases or with particular non-health-related traits. The aim of this study was to collect information regarding the awareness, experiences and attitudes of European clinical geneticists about genetic tests and test interpretations sold directly to consumers. European clinical institutes where genetic counselling is offered to patients were contacted. One-hundred and thirty-one of the three-hundred eligible respondents (44%) answered a questionnaire. Eighty-six percent (110/128) of the clinical geneticists said they were aware that companies are advertising and selling genetic tests directly-to-consumers. Of the 44% (54/121) of the respondents who had been contacted by patients who underwent DTC testing, almost all respondents (98%, 47/48) did discuss test results with the patients. The following respondents somewhat or strongly agreed that DTC genetic tests should be legally banned for following tests: prenatal gender tests (69%, 77/112); genome scans (63%, 70/112), 54%, athletic performance (54%, 61/113), preconceptional carrier tests (53%, 59/112) and ancestry testing (27%, 30/113). The results indicate that most European clinical geneticists have only limited experience with patients who have accessed direct-to-consumer genetic testing, however, these physicians are entering into patient-physician interactions with patients when requested to do so.
I’m going to calm down, because these results frankly kind of piss me off. 30 out of 113 think ancestry testing should be legally banned? The stuff quoted in ScienceDaily is even more disturbing:
“Genome-wide scans by companies are totally unacceptable, as they can derive sensitive information about medically relevant conditions and will also provide lots of information which is difficult to interpret, even for medical professionals,” said another respondent. Presenting the results of such tests directly to individuals is unacceptable, the majority of those surveyed said.
90% of respondents felt that a pre-symptomatic test — predicting if an asymptomatic person had a very high probability of developing a condition — should not be allowed without face-to-face medical supervision; 93% felt the same for a predictive test for a condition that has a penetrance (the proportion of individuals with the mutation who exhibit clinical symptoms) of 50 — 60%; 79% for a carrier test for homozygous monogenic disorders, such as sickle-cell anaemia; and 72% for a predictive test for a condition that increased or decreased a person’s risk of developing it by 4% when compared to the general population.
At the moment, DTC genetic tests reach the market without having undergone any form of regulation. “Better regulation is needed at the level of market introduction of these tests,” says Professor Borry. As in the case of drugs, a procedure should be developed for genetic tests.
I think one of the key issues is that these genetic professionals view DTC genomics in the same category as a pharmaceutical. I view DTC genomics as part of the same family of consumer and social goods as information technology. When viewed in the context of our current medical-industrial infrastructure it seems that on the margin the future opportunities to reduce morbidity through better lifestyle choices and more information via DTC genomics is a no brainer. If there was social science evidence that people who receive false positive results are regularly committing suicide then obviously my preference for loose regulation would need re-examination. That would be like someone jumping off the tenth floor of an office building after a “blue screen of death.”
But from what I’ve seen at places likes Genomes Unzipped and FuturePundit these dystopian visions of mass hysteria don’t end up to panning out. Until that point it seems that the best avenue toward improvement of this technology is to allow the trial and error process of innovation to continue. It is incumbent on those of us “in the know” to evangelize about the limitations and opportunities of this technology (e.g., don’t buy AIBioTech Sports X Factor!). But the reality is that much of medicine is already technology, and not subject to careful professional oversight. Instrumentation necessary for life critical functions are designed and built by engineers and technicians.
The bigger social issue here seems to be the attempt by genetic professionals to regulate the flow of information. Though I’m skeptical of most licensing regimes I’m not totally opposed to them on principle. But they need to be imposed on extreme cases only. You don’t want just any random person offering cut rate surgery or mass prescribing antibiotics to one and all. The individual and social costs of these actions can be very negative and irreversible (i.e., someone dies, or a resistant bacterial strain emerges). But when it comes to information services requiring a “professional” is going to choke the supply and spike up the cost. Additionally, there’s going to be a constant latency in terms of the ability of professionals to actually interpret the swell of data which is going to be coming in their direction. The reality is that the professionals are going to have to rely on advanced analytic software. Obviously my own preference is that such analytic software should be widely available and cheap. If you want to ban sex selective abortions address the problem at the level of abortion, a procedure which most people agree should be under some professional and regulatory supervision already. Don’t deny people the information to prevent a few harms.
If anyone wants to release their genotype into the public domain, email me at contactgnxp -at- gmail.com. Know that some clinical geneticists probably think you’re a public health hazard!
Razib Khan’s degrees are in biochemistry and biology. He has blogged about genetics since 2002, previously worked in software development, is an Unz Foundation Junior Fellow and lives in the western US. He loves habaneros.
May 31st, 2011 at 10:31 am
p.s. at some point within our lifetimes i think a lot of basic ‘surgery’ will be automated.
May 31st, 2011 at 11:11 am
The results in the first abstract don’t offer much (anything) new to what we already know, prediction of common disease based on just a few genetic variants is not very accurate right now. In my case I have the TT (higher risk) version of the TCF7L2 SNP associated with Type 2 diabetes. A few years ago DeCode sold a test based on just this gene:
a) DeCode 2007 tell me i have a 2-fold increased risk
b) DeCode 2010 say it is 1.35x increased
c) 23andMe 2010 tell me it is 1.23x increased
d) The Corriell trial (one diabetes gene!) would tell me I am at lower risk
e) Dodgy Italian test tells me my risk is “much higher than average”
None are right and none are wrong (except the last one) – all are population statistics and none apply to me as an individual. My actual risk is close to zero: I have normal BMI, exercise enough and eat hardly any refined carbs. There are many areas where the DTC companies could improve their marketing and their interpretations (they should stop saying “your risk” for example, it’s not MY risk – it’s a population based number).
As for the survey – big news, professionals want to protect their patch. Plumbers, electricians, carpenters, car mechanics etc would probably welcome a ban on DIY. So we should ban access to all information that informs us about disease and gives us tools to calculate risk – including WebMD and the rest. In Italy you can only buy aspirin from a qualified pharmacist, the result is that a headache costs me 4 euros for a pack of 12 pills – guess what? they voted against OTC medicines being sold in supermarkets.
May 31st, 2011 at 1:11 pm
Keith is right: nothing new here! Everybody knows the limitations of these tests!
However, banning them is not a solution. If MDs are not able to interpret them, then they should study more genetics and statistics. Or otherwise they should allow other professionals to deal with this subject!
Instead, they choose to remove these tests completely, not considering the fact that people *are* interested in knowing their own genome! These tests need to be improved, not banned. Also, they must be somehow regulated in order to avoid that rubbish tests reach the market.
Unfortunately, it looks like nobody cares about improving the risk prediction models, about improving the communication of results, about integrating them with environmental factors. It’s too easy to simply say “Ban them!” without carefully studying all the aspects of the problem.
May 31st, 2011 at 1:21 pm
I wouldn’t say “nobody cares about improving the risk prediction models, about improving the communication of results, about integrating them with environmental factors” — there are definitely groups out there that are very focused on all three of those issues. The unfortunate part is that one side’s solution is to not give the other side even a chance to improve on things that traditional medicine itself could stand to improve: prediction models, communication, and integrating information from multiple sources.
May 31st, 2011 at 1:32 pm
[...] SportsXFactor by Razib Khan in Biotech, Genetics, Genomics, Personal Genomics | 4 comments | RSS feed | [...]
May 31st, 2011 at 1:33 pm
re: #3, #4, it’s early days yet! again, let’s keep the technology model in mind.
May 31st, 2011 at 1:58 pm
@Shirley Yes I mean that.
These big experts prefer to ban the tests rather than asking for a better service for people. I’m afraid Keith is right, they just want to protect their patch.
May 31st, 2011 at 6:48 pm
within our lifetimes i think a lot of basic ‘surgery’ will be automated
This is a misunderstanding. All the talk about robotics in surgery is misunderstanding. Robots perform exactly the same function as 19th-early 20th century machines did in trades. Robots cut flesh more precisely than humans do. Big deal – machines drill wood more precisely than humans, too. But it is still a surgeon who decides where to cut and how deeply. No robot supplants this function. There is no such thing as a “standard” surgery that is identical between different patients.
Unless you believe that AI is coming within your lifetime. In which case I have a nice bridge in Brooklyn to sell to you.
May 31st, 2011 at 7:56 pm
This is a misunderstanding. All the talk about robotics in surgery is misunderstanding.
oh thanks, i had no idea you had such a perfect command of my thought processes
May 31st, 2011 at 10:38 pm
Good article. Thank you.
I try to avoid the “S” word (socialism) so as to not polarize the issues more yet, but sometimes it’s necessary to call a spade a spade.
At the risk of showing my cynicism: one point to keep in mind is that those of a socialist mindset will gravitate towards socialistic measures to solve problems (even those caused by socialism). As a generalization, I’d be amazed if the Europeans ended up endorsing a freedom-based approach, even though market forces tend to be vastly more effective and efficient than government regulations at fostering realistic and appropriately diverse and context-specific levels of quality. I’m taking it as a given that the pro-socialism crowd is ignoring the key moral issue, i.e., that these aspects are for the private parties to negotiate, not legislators. Even then, the market-based solutions are better.
Biotech isn’t all I do, and I observe massive problems with government regulations even in relatively crude industries, where the government regulations are ham-handed and destructive (i.e., not just government regulation, but immensely clueless and shortsighted government regulation). If we’re going to have regulation (and we shouldn’t, but IF) then it should at least be well-pondered enough, and make enough sense, to not fall apart at the first exposure to common sense as applied by an industry insider. If the legislators can’t get it right even with such crude industries, it’s probably time to be very worried about the cluelessness about to be unleashed onto the DTC industry. It’s sort of like seeing someone unable to do a good job of slicing an apple, and next he’s about to perform brain surgery on a patient. It doesn’t bode well.
The “ban them all” approach has approximately the same level of fairness as “kill ‘em all, let God sort it out.”
Then again, there’s a lot to be said for consistency. If things are to be banned because they are imprecise and because their mistakes could cost lives, then certainly every socialist legislative body, and resultant government agency, should be banned for those reasons.
Andre Gous
CEO
Precision Quality DNA
May 31st, 2011 at 10:47 pm
I try to avoid the “S” word (socialism) so as to not polarize the issues more yet, but sometimes it’s necessary to call a spade a spade.
well, i think the key here is a bias toward regulatory precaution due to concerns with liability, as well as regulatory capture by interested parties. real socialist societies where the state commands substantial means of production aren’t actually too obsessed with stuff like consumer protection, because they’re geared toward production. e.g., the eastern bloc and china has really bad environmental outcomes.
in other words, the real issue is an excessive faith in the technocracy in planning and guiding progress to minimize all downside liabilities while maximizing the upside gains from innovation.
June 1st, 2011 at 2:59 am
I think the best approach is still that proposed by the Human Genetics Commission (HGC) – http://www.hgc.gov.uk/Client/news_item.asp?NewsId=147
It is sensible and pragmatic, by a body that has been analysing DTC genetics for longer than any other, having started way back in 2002 with a Committee headed by Sir John Sulston. Over the years the wide and varied committee membership has changed but surprisingly they have continued to come up with consensus statements which, in my opinion, almost always hit just the right notes (e.g. Preconception diagnosis http://www.hgc.gov.uk/Client/news_item.asp?NewsId=156)
There is little talk of banning anything but the principles would give protection where it is needed without stifling progress and there is no hint of either paternalism or attempts at professional control
June 1st, 2011 at 4:09 am
What paternalistic claptrap.
How dare they
June 4th, 2011 at 9:43 am
[...] both MacArthur and Razib Khan of Gene Expression note, the appropriate question to ask is not whether clinicians believe genetic tests are harmful [...]