DNA could be a hash sequence

Plausibility of the DNA sequence for the encryption

A major problem with modern biometric authentication is the fact that things like your fingerprint are used as a password. Unlike a real password, a fingerprint is not secret enough. Biometric identities can be used for user names that only need to be unique to you, but not passwords. There are a few problems with using DNA as a private key or other secret value:

  • They leave exact copies of your DNA on everything you touch.
  • The human genome doesn't vary very much, which makes brute force a risk.
  • People you are related to have an even more similar genome.
  • DNA actually changes over time in an individual, so it is not static.
  • You cannot revoke your DNA and change it after a compromise.

You leave your DNA everywhere

A good private key or password is something you have knowledgethat you have to voluntarily disclose. "Private key" means that the key must remain secret and its knowledge enables someone to identify themselves as the original owner. Unlike a password-encrypted private key on your laptop, you leave your DNA everywhere. In your breath there are excretions, skin cells falling off millions of times, oil, hair, saliva, tears, etc. This makes it pointless for a private key which, as the name suggests, has to be kept secret.

From a recent case in which DNA was used to incriminate a person, three judges pointed to the risk to personal privacy if accidentally left DNA can be used as evidence in a criminal case. Regardless of the outcome of this review, the fact that we are leaving the DNA is still there:

Majority approval of such a police process essentially means that a person who wishes to keep their DNA profile private must conduct their public affairs in a hermetically sealed protective suit. In addition, the majority view is likely to make many people reluctant to go to the police station to voluntarily provide information about crimes for fear that it will also be included in the CODIS database. Majority ownership means that a person can no longer vote, join a jury or obtain a driver's license without opening their genetic material for state collection and codification. Unlike DNA left behind in a park or restaurant, these are all cases where the person has identified himself to the government agency.

It doesn't matter whether the government decides whether or not this evidence is admissible. What matters is the fact that the evidence in the form of DNA is primarily left for anyone to take and analyze. Worse still, once your DNA is "compromised" it cannot be revoked!

The (missing) genetic variation in humans

Only a tiny fraction of DNA differs between individuals. While DNA itself contains a lot of information, each will prototypical human genome dem Your Genome come very close. If you're using your genome for cryptographic purposes, the differences are so small that brute force becomes possible. In other words, there is just too little difference between us. Not only that, but your family becomes an even more have a similar genome. Even if random genetic variations were large enough to prevent an exhaustive search, do you really want only your two parents to give up their genome in order to be able to "compute" your genome? Or your siblings?

A large number of human genetic differences arise from so-called SNPs or single nucleotide polymorphisms. These are single bases in DNA that are known to vary between people. There are currently only a few hundred million known polymorphisms. While a hundred million may seem huge, people who are ethnically related will have far fewer genetic differences. A good key is equally different between users, whether or not they are related by family or race.

Jumping genes (transposable elements)

There is another problem. If you analyze the DNA down to every single base pair, you will find that it actually changes over time! Small self-reproducing elements called transposons are sequences that copy themselves and reinsert themselves in different areas of our genome. They do this slowly and rather randomly. Over time, this means that even our individual cells do not have the same DNA as when we were born. Likewise, even identical twins do not have completely identical DNA because of this phenomenon. This is not a problem for most modern genetic sequences, where only certain variations of certain genes (alleles) are mentioned, but a problem for anything that requires precise accuracy down to the individual base pair. 40% of the DNA is transposable!

DNA as a unique identifier

For what could Your genome will be used? Identification and authentication. While it is very easy to discover your DNA sequence, it is impossible to copy it into someone else's body. No matter how much I try, when a single cell is extracted from me and its DNA is analyzed, it shows the DNA I had at birth (with no jump genes), not your DNA. This makes it possible, with sufficiently careful DNA examination, to prove who a person is, who they say they are. It's like an SSN, but much, much harder to use for identity theft. If you know your DNA, you can't pretend to be that.

DNA isn't the only thing that can be used for identification. The pattern of the veins in your hand is unique to you and, unlike fingerprints or DNA, doesn't linger anywhere on anything you come in contact with. You have to explicitly place your hand on a vascular scanning device that is less intrusive than a retina scan. This is actually a technique that is used in Japan. While this is still more private than DNA, it is still better used as a username than a password as it can still be accessed stealthily.