One simple immediate consequence may be that you cannot answer a question like "do you have any reason to believe that you may be at risk for XYZ" anymore without potentially having to rely on a result that may or may not have statistical significance -- or which you may have misunderstood. A lot of 23andme reports are in the form of "if you are east asian and have the following genotype for SNP rsXXXXXX, you have a 3% chance of developing condition XYZ". Personal genomics services like 23andme are going out there and saying that SNPs are pretty reliable, but the reality for some conditions and traits may still be fuzzy as more data comes in. There may be as-yet undiscovered SNPs that have a bigger effect on your cancer risk than the ones their v3 chip happens to cover, for example, and just having a 1 or even a dozen SNPs may not be enough for a clear picture. On the other hand, an insurance company might find it risky enough to deny you coverage. Nobody knows how that will shake out.
In the future, if a given insurance provider knows you have purchased a service like this, they also can then figure out which SNPs you know your genotypes for (it would be fairly trivial for any insurance company to find out which 950,000 or so SNPs 23andme tests for), and can then craft a survey form asking about these specific traits.
Many people will likely still try the service anyway because they'd rather know, pro-actively address certain issues, and risk the insurance game, than not know at all.
[EDIT: Apologies for not having read your question all that clearly. Just assume the above applies to "admitting you've used the service in public"]
> potentially having to rely on a result that may or may not have statistical significance
I can't stress this enough. I've had a bunch of friends buy the 23andme kit while it was on sale recently because they were interested in my results from a while ago, and their buildup to getting their own results was "what if it tells me I'm never going to have x?!" and things like that. Kind of frustrating to explain how it works.
23andme put me at average to low risk of a few things they test for that I have in real life. One of the more frustrating things to read was that 23andme declared from preliminary asthma research that I was at lower than average to average odds, when in my past I've had severe asthma I've even been hospitalized for.
On the flip side of things, 23andme determined my risk of melanoma from genetics is 0.1% (as compared to 1.7% average). But I live in Los Angeles and I get sunburnt/suntanned multiple times a year, not to mention the sheer number of hours I spend outdoors in general. I regularly track skin changes and visit a dermatologist once in a while because new spots and changes on my skin stress the hell out of me. I know my risk likely skyrockets past the 1.7% easily if you take my environment into account.
Insurance companies already play this risk/percentage game anyway with lots of other information, and I don't think I see a big of a risk as people being denied insurance from testing like this. If anything, it means everyone can be more proactive and save money and lives in the end. (Of course, I am being pretty naively optimistic here...) I mean, I imagine that's what they're trying to do on some level when they send me pamphlets about STD testing and prenatal care in the mail every other week just because they know I'm a 20something female on birth control.
In the future, if a given insurance provider knows you have purchased a service like this, they also can then figure out which SNPs you know your genotypes for (it would be fairly trivial for any insurance company to find out which 950,000 or so SNPs 23andme tests for), and can then craft a survey form asking about these specific traits.
Many people will likely still try the service anyway because they'd rather know, pro-actively address certain issues, and risk the insurance game, than not know at all.
[EDIT: Apologies for not having read your question all that clearly. Just assume the above applies to "admitting you've used the service in public"]