But the hash of health data isn't informative. It doesn't make sense for a doctor to view, for example, the hash of a blood test result. They need to see the actual result, not its hash. The same thing is true of DNA sequencing results. The only thing I could learn from the hash of a DNA sequence is that it's different from one I have in a database. But I need to know exactly how it is different -- precisely the clear text content of the sequence -- for that to be useful information for a patient or for research.