3 ms·

The sarcastic tone of your response suggests that you're expecting me to be an idiot and/or a hypochondriac. I may or may not be a typical 23andme customer (an

by dgacmu 10y ago

The sarcastic tone of your response suggests that you're expecting me to be an idiot and/or a hypochondriac. I may or may not be a typical 23andme customer (and wasn't suggesting I was), but we had very specific, actionable reasons for using their services: Of course we didn't do a second scan, that would be silly. My wife carries some recessive genes for inherited conditions common among Ashkenazi jews, and because I don't know half of my ancestry, we simply wanted to confirm that I was negative for them. They're not particularly common, hence "no surprises." Checking the embryo for diseases such as Tay-Sachs typically require chorionic villus sampling, which comes with a 1-2% risk of causing a miscarriage. Spitting into a tube and sending it for SNP testing is cheap, easy, and low-risk. Had I been a carrier, we would have had CVS performed. The 23andme results let us safely skip having an extra procedure performed. Net win. (Note that this is not going out on a limb: screening for Tay-Sachs is strongly recommended by ACOG when both parents are known to be carriers.) There are screening panels designed to specifically hit only the carrier status markers we were interested in, but for me, the extra ancestral information tipped the scale in favor of the more general information.

jacquesm 10y ago
23andme does not sell clinical diagnostic services, period. If you are going to make really important decisions regarding your health or that of your descendants then you should really look elsewhere. You're not capable of interpreting the results and without a second scan you don't even know if the results are yours. This is really not an area where - unless you are qualified in the field - you should 'self medicate', the risks are way too large. > The 23andme results let us safely skip having an extra procedure performed. I think you're putting much more faith in them than is warranted, and that's where for me the risk lies of services like these (besides the very obvious privacy issues). > (Note that this is not going out on a limb: screening for Tay-Sachs is strongly recommended by ACOG when both parents are known to be carriers.) Yes, it is.
- dgacmu 10y ago
  You keep making statements referring to _me_ that are inaccurate, but would be correct if you scoped them to "the average consumer" or "an untrained individual." First, I've got more than enough biology training to interpret it - a bachelors + a small amount of graduate study looking at analysis of chip-based genetic and protein assays. (Not my day job. I certainly wouldn't claim to be qualified to do this for anyone else.) Second, I certainly do have high confidence that the results are mine. That's actually one of the cool things about a larger assay: I spotted a second cousin in the ancestry components of the list, and the maternal components match exactly with what I know. The remaining issue is simply knowing what their false positive & negative rate is on the carrier status reports. I don't know, but given that we have a pretty good prior that I wasn't likely to be a carrier, it was sufficient for our purposes. (And, in fairness to 23andme, that's one part the FDA is letting them continue to provide.) All of the concerns you've expressed make sense in general. I absolutely wouldn't encourage anyone to do this without talking to their doctor.
  - jacquesm 10y ago
    So, then maybe if you're so exceptional you should state these things up front rather than to add them afterwards to bolster your position. 23andme is there for the general consumer, not for you specifically. Of course there are exceptions to every rule, I'm well aware of that and accept that there may be some extreme edge cases for which 23andme makes sense. But you make it seem like your situation is 'normal satisfied consumer' at first and then add more and more information to move it into 'extremely exceptional satisfied consumer' territory. > I spotted a second cousin in the ancestry components of the list, and the maternal components match exactly with what I know. http://jacquesmattheij.com/if-you-have-nothing-to-hide http://jacquesmattheij.com/if-you-have-nothing-to-hide
nommm-nommm 10y ago
>Of course we didn't do a second scan, that would be silly... I don't know half of my ancestry, we simply wanted to confirm that I was negative for them Oh god I hope you are not serious. These services are not clinical diagnostic tests and shouldn't be used as such for a thousand different reasons. Genetic counseling is serious business. It should be administered by a trained professional in a medical setting. The results of any genetic tests should be interpreted by a trained professional.
- dgacmu 10y ago
  See below. I'm completely serious. The population prevalence of Tay-Sachs is about 0.4%. (I don't look obviously Ashkenazi - quite the opposite - so there's little reason to assume I'm in a high-risk population). Therefore, there's a pretty strong prior that we didn't need to worry about it in the first case. Even assuming that the 23andme results have a horrible false negative rate -- let's say they miss 25% of carriers -- a negative result on a single screen (where we know it was actually my data, as Jacques noted) is enough to drive our per-child risk down to about 1 in 4000. The false positive risks are small - follow-up genetic testing using a certified lab is easy. Note that I was creating a deliberately absurdly high number for that false negative rate. The FN rate found, for example, for 23andme's Bloom Syndrome carrier status test is much lower than what I used above. The actual post-test carrier risk when I calculated it was under 1 in 10,000. Perfectly fine for a low-risk situation like ours.
- burfog 10y ago
  "trained professional in a medical setting [...] trained professional." This implies that you oppose testing, because with those expenses it's just not happening. Nobody likes to pay a 4-digit sum to look at a dozen spots on the genome, and then another test and another 4-digit sum to look at a few more (separate office visit of course), and then again...
  - nommm-nommm 10y ago
    I don't opposite genetic testing, I am in full support, especially as someone who is a carrier of a very rare genetic disorder. It is serious though it shouldn't be a DIY thing just like MRIs or any other medical tests.

by dgacmu 10y ago

jacquesm 10y ago

23andme does not sell clinical diagnostic services, period. If you are going to make really important decisions regarding your health or that of your descendants then you should really look elsewhere. You're not capable of interpreting the results and without a second scan you don't even know if the results are yours. This is really not an area where - unless you are qualified in the field - you should 'self medicate', the risks are way too large. > The 23andme results let us safely skip having an extra procedure performed. I think you're putting much more faith in them than is warranted, and that's where for me the risk lies of services like these (besides the very obvious privacy issues). > (Note that this is not going out on a limb: screening for Tay-Sachs is strongly recommended by ACOG when both parents are known to be carriers.) Yes, it is.

dgacmu 10y ago
You keep making statements referring to _me_ that are inaccurate, but would be correct if you scoped them to "the average consumer" or "an untrained individual." First, I've got more than enough biology training to interpret it - a bachelors + a small amount of graduate study looking at analysis of chip-based genetic and protein assays. (Not my day job. I certainly wouldn't claim to be qualified to do this for anyone else.) Second, I certainly do have high confidence that the results are mine. That's actually one of the cool things about a larger assay: I spotted a second cousin in the ancestry components of the list, and the maternal components match exactly with what I know. The remaining issue is simply knowing what their false positive & negative rate is on the carrier status reports. I don't know, but given that we have a pretty good prior that I wasn't likely to be a carrier, it was sufficient for our purposes. (And, in fairness to 23andme, that's one part the FDA is letting them continue to provide.) All of the concerns you've expressed make sense in general. I absolutely wouldn't encourage anyone to do this without talking to their doctor.
- jacquesm 10y ago
  So, then maybe if you're so exceptional you should state these things up front rather than to add them afterwards to bolster your position. 23andme is there for the general consumer, not for you specifically. Of course there are exceptions to every rule, I'm well aware of that and accept that there may be some extreme edge cases for which 23andme makes sense. But you make it seem like your situation is 'normal satisfied consumer' at first and then add more and more information to move it into 'extremely exceptional satisfied consumer' territory. > I spotted a second cousin in the ancestry components of the list, and the maternal components match exactly with what I know. http://jacquesmattheij.com/if-you-have-nothing-to-hide http://jacquesmattheij.com/if-you-have-nothing-to-hide

nommm-nommm 10y ago

>Of course we didn't do a second scan, that would be silly... I don't know half of my ancestry, we simply wanted to confirm that I was negative for them Oh god I hope you are not serious. These services are not clinical diagnostic tests and shouldn't be used as such for a thousand different reasons. Genetic counseling is serious business. It should be administered by a trained professional in a medical setting. The results of any genetic tests should be interpreted by a trained professional.

dgacmu 10y ago
See below. I'm completely serious. The population prevalence of Tay-Sachs is about 0.4%. (I don't look obviously Ashkenazi - quite the opposite - so there's little reason to assume I'm in a high-risk population). Therefore, there's a pretty strong prior that we didn't need to worry about it in the first case. Even assuming that the 23andme results have a horrible false negative rate -- let's say they miss 25% of carriers -- a negative result on a single screen (where we know it was actually my data, as Jacques noted) is enough to drive our per-child risk down to about 1 in 4000. The false positive risks are small - follow-up genetic testing using a certified lab is easy. Note that I was creating a deliberately absurdly high number for that false negative rate. The FN rate found, for example, for 23andme's Bloom Syndrome carrier status test is much lower than what I used above. The actual post-test carrier risk when I calculated it was under 1 in 10,000. Perfectly fine for a low-risk situation like ours.
burfog 10y ago
"trained professional in a medical setting [...] trained professional." This implies that you oppose testing, because with those expenses it's just not happening. Nobody likes to pay a 4-digit sum to look at a dozen spots on the genome, and then another test and another 4-digit sum to look at a few more (separate office visit of course), and then again...
- nommm-nommm 10y ago
  I don't opposite genetic testing, I am in full support, especially as someone who is a carrier of a very rare genetic disorder. It is serious though it shouldn't be a DIY thing just like MRIs or any other medical tests.