What 23andMe is offering is to make people’s exomes available to them, and the DNA sequencer will go over their DNA 80 times (known as 80-fold coverage) to make sure that the genetic code is accurate. This is stunning because a year ago this would have cost ten times as much or more. 23andMe isn’t the first company to offer consumers exomes — that would be Knome, of Cambridge, Mass. — but still the low price is eye-popping. It’s also a lot more data than the DNA chips 23andMe has used up until now, which capture single-letter changes in genetic code scattered across the genome.
What is an exome? Your exome is the 50 million DNA bases of your genome containing the information necessary to encode all your proteins