Genetics prof: Why I won’t waste my money on a DNA test in 2014

http://www.venturebeat.com/2013/12/31/genetics-prof-why-i-wont-waste-my-money-on-a-dna-test-in-2014/

by linux_devil • 13 years ago

27 31 13 years ago

Drifter• 13 years ago

I got a genetic test done with 23andme. It said I had a (greater probability of a) warfarin sensitivity. This was interesting because my grandma had a stroke after being given warfarin. The stroke put her in a wheelchair for the rest of her life - it ended her independence and she had to go into a home with 24hr care. It was horrible.

After this I got my entire family tested. As expected my mother carried the warfarin gene (the grandma was on her side of the family).

Knowing this information is hugely valuable to me. I think it's awful that the FDA deems fit to prevent me getting information about myself.

freehunter• 13 years ago

The problem becomes apparent if someone is "diagnosed" by 23andme as having a predisposition to something that they don't actually have. For example, your test says you're sensitive to warfarin and you choose not to have that drug administered in a time when your doctor says it would be the best option. Not only are the results questionable, perhaps warfarin is the only good option. If you refuse it based on an invalid test and you are seriously damaged by the lack of proper care, that's a problem.

I'm no expert, but it seems like the validity of these tests are being drawn into question. While it may help, it may also really hurt. Questioning these interpretations is exactly what medical science should be doing. You're not getting information about yourself, you're getting (to you) incomprehensible data and a guess as to what it means. Is that more valid than the family history that your doctor already has?

Humans tend to make emotional decisions when it comes to their own health. The goal of medical science is to get past the emotion (look at what this drug did to my grandma) and find provable facts instead.

dnautics• 13 years ago

For example, your test says you're sensitive to warfarin and you choose not to have that drug administered in a time when your doctor says it would be the best option.

Then you repeat the test. Your doctor may not have been considering that you may have a warfarin sensitivity, the doctor's family history may be incomplete, etc. etc. This is especially an issue with minority communities, whose medical issues are not as well dealt with by physicians, or medical science in general (minority = fundamentally less statistical strength). It's not a well-known fact, for example that asians tend to have statin sensitivity because of impaired clearance, a lower dose is equally effective in asians (although IIRC while effective in reducing cholesterol, endpoint efficacy of statins in preventing coronary disease is unknown in asians); to my horror I found my father was being prescribed the 'caucasian' dosage of statins, and then a year later, I took the 23andMe test and found that I'm homozygous to a codominant allele that is associated with dramatic increase the risk of myopathy when taking simvastatin. So here my dad is taking an inappropriate dosage of a drug that is likely making him sicker and maybe not even helping prevent coronary disease.

Now, the question you have to ask yourself, is, is it worth it to deny responsible people like myself the power to easily and cheaply obtain these sorts of decisions just to protect people who are going to get hysterical about information, even when there's a second layer of professional expertise that intervenes before any medical action is taken?

look at what this drug did to my grandma

But that is exactly, scientifically valid evidence. I think you are placing an unreasonable reverence on the 'validity' of medical 'facts' or the competence of medical authorities. After all, proper scientists aren't necessarily seeking provable facts but rather, disprovable assertions.

MichaelGG2• 13 years ago

The FDA is _not_ trying to prevent this information. It's trying to prevent 23andme from marketing a diagnostic product that doesn't meet diagnostic regulations.

They can't have it both ways. They can market and dump out your DNA data. Or they can meet regs, prove they are clinically accurate, then market it as a diagnosis product.

We'd not like random companies starting up and misleading people and claiming to diagnose but really just flip a coin. That's all the FDA is asking.

barry-cotter• 13 years ago

The diagnostic regulations are too stringent . They are preventing people from getting information that they want to pay for, 23&me is willing to provide, and that 23&me can justify. It's not like they're taking information straight off of SNPedia, they survey the literature on the alleles of the henes they test.

dzhu2• 13 years ago

Warfarin sensitivity is _precisely_ why 23andMe needs to be regulated; 23andMe has NOT clinically (or analytically) validated any of the claims around the specific SNPs they've identified. All 23andMe does is link to research papers that may suggest that there are gene variants that are linked to warfarin sensitivity; however, these have not been validated to be clinically significant.

In fact, just last month, the New England Journal of Medicine published a landmark study around the pharmacogenomics of warfarin dosing, which found that this very genetic data does NOT affect/improve warfarin dosing (http://www.nih.gov/news/health/nov2013/nhlbi-19.htm, original paper: http://www.nejm.org/doi/full/10.1056/NEJMoa1310669). In light of this, this warfarin sensitivity information that you've obtained from 23andMe is almost certainly a false positive, and if you were on a prescribed warfarin treatment, 23andMe would've likely resulted in a change in your behavior that would be strictly detrimental to your health.

mindcrime2• 13 years ago

In light of this, this warfarin sensitivity information that you've obtained from 23andMe is almost certainly a false positive, and if you were on a prescribed warfarin treatment, 23andMe would've likely resulted in a change in your behavior that would be strictly detrimental to your health.

I don't think there is any valid basis for that claim. A rational person (and I only mean "somewhat rational", I'm not talking about an Econ101 "perfectly rational actor" here) would get their 23andMe results, go "hmmm, this is interesting" and line up a visit to their primary care physician to talk about the results, and what it might mean for their treatment... at which point additional tests might be indicated, or the doctor could more fully explain the various tradeoffs, implications, etc.

There's no particular reason to assume that people are going to randomly adjust their medications based on 23andMe results alone.

And, even if they do, so be it - the price of personal freedom is individual responsibility for the outcome of your actions.

Cass2• 13 years ago

This comment is the perfect example of why the FDA needs to be involved with this. They gave you very important medical information. Did they a) make sure the information was accurate and b) explain it to you in a way that's understandable to a layperson?

I can easily see a layperson reading that, and thinking "warfarin sensitivity"? As in "food sensitivity", meaning "this is something that isn't good for me, and I should avoid it?" Wait, isn't that the stuff that gave my grandmother a stroke? Holy shit, they killed my grandmother by giving her too much of a medicine that she's sensitive to!"

All warfarin sensitivity actually means, though, as far as I understand it, is that you're likely to need a lower dose than the average patient. If your grandmother had a stroke, it's unlikely that she was overdosed, though - in fact, it's quite likely that she received too low a dose.

If someone has a stroke under warfarin treatment, there are two likely causes: Either their warfarin dose was too low, or they had an artery-to-artery embolic stroke instead of the cardioembolic stroke the warfarin was supposed to prevent. (There are of course other, more rare cases of stroke, but those are the two big ones.)

Do you see how there's a huge potential for misunderstandings here? I'm not saying you suffered this particular misunderstanding, or that laypeople should be stopped from getting this information. I'm just saying, if you're going to put something like that out there and claim it's a diagnostic tool, it needs to be accurate and it needs to be explained, and that's where the FDA needs to come in.

temphn• 13 years ago

Hank Greely is not a "genetics prof", he is a bioethicist in Stanford's Law School. He doesn't develop new genetic technologies. This is like calling a film critic a director.

http://www.law.stanford.edu/profile/hank-greely

Snail_Commando5• 13 years ago

"Hank Greely is not a "genetics prof", he is a bioethicist in Stanford's Law School. He doesn't develop new genetic technologies. This is like calling a film critic a director.

http://www.law.stanford.edu/profile/hank-greely "

I'm not sure your assessment is entirely correct.

Here's an excerpt from the same page you linked to:

"Greely is also a professor (by courtesy) of genetics at Stanford School of Medicine."

I don't know how professorships by courtesy work at Stanford.

https://en.wikipedia.org/wiki/Professors_in_the_United_State...

Assuming that the content currently in that section of Wikipedia is correct and is congruent with how things work at Stanford, he is a "genetics prof".

Or we can just take his Stanford bio at face value.

Also, we should consider what the man has to say. Whether or not he "develop[s] new genetic technologies" is irrelevant if his opinions are valid and his facts are correct. If you take issue with the opinions he has or the facts he states, then address those head on.

The man's thoughts are being called upon because he is a domain expert in bioethics (and, as we've just found out, genetics). I think it would be a good bet that this man has a wealth of relevant domain knowledge with respect to state of the art genetics research, gene sequencing technologies, and genomics startups.

Qualification sniping tends to be a poor way of discounting what someone has to say.

patrickg_zill2• 13 years ago

It seems extremely, extremely clear from the page you linked ... look at the sidebar: Education: BA 1974 from Stanford, Law Degree.

He is a lawyer, and did not even get a science-related degree when he took his bachelor's (BA = Bachelor of Arts).

daemonk• 13 years ago

Were the raw data consistent? I can understand that the 3 companies were interpreting the raw data differently, but were the underlying snp frequencies consistent?

If they are not consistent, then the whole thing is pointless and they need to work on better kits. If they are consistent, it still doesn't say much.

Genome wide association studies (GWAS) are very hard to control. And most papers tend to ignore external factors when they conduct the analysis. Do these group of people have this phenotype because of particular snps or do they have it because they have similar diets, similar geographic area, similar age range?

tehwalrus• 13 years ago

not a genetics prof - a law prof.

http://www.law.stanford.edu/profile/hank-greely

Snail_Commando5• 13 years ago

"not a genetics prof - a law prof.

http://www.law.stanford.edu/profile/hank-greely "

From the page you linked:

"Greely is also a professor (by courtesy) of genetics at Stanford School of Medicine."

It seems that he is a Professor (by courtesy) of Genetics, he is on the Steering Committee for Biomedical Ethics, and is a director at the Center of Law and the Biosciences.

Here is my other comment on the matter:

https://news.ycombinator.com/item?id=6994518

sampo• 13 years ago

Normally you would assume that if someone is a genetics prof., they would have some formal training in genetics. Which in this case is not true. He was trained in a law school, but is now cooperating with genetics and medicine people.

Genetics prof: Why I won’t waste my money on a DNA test in 2014

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