[beaugunderson]

23andMe uses a SNP array, or SNP chip, to look at SNPs (single-nucleotide polymorphisms, or more generally, single nucleotides that vary within a population). Basically what it gives you is a diff against a reference genome. So yes, while not a full genome sequence you can still get a VCF file out of it, impute sites that are not on the chip, use it for genealogy analysis, look at someone's disease carrier status, genetic disease likelihood, etc.

[dash2]

Yeah, I mean this is about 1 million SNPs, right? It's very very personal indeed. I could make good guesses at the chance of you going to university; your height; your risk of depression; what you look like....