KentuckyFC writes "Since the mid 90s, researchers have been using DNA to carry out massively parallel calculations which threaten encryption schemes such as DES. Now one researcher says that if DNA can be used to attack encryption schemes, it can also protect data too. His idea is to exploit the way information is processed inside a cell to encrypt it. The information that DNA holds is processed in two stages in a cell. In the first stage, called transcription, a DNA segment that constitutes a gene is converted into messenger RNA (mRNA) which floats out of the nucleus and into the body of the cell. Crucially, this happens only after the noncoding parts of the gene have been removed and the remaining sequences spliced back together." (More below.)
KentuckyFC continues: "In the second stage, called translation, molecular computers called ribosomes read the information that mRNA carries and use it to assemble amino acids into proteins. The key point is that this is a one way process. Information can be transferred from the DNA to the protein but not back again because during the process various details are lost, such as the places where the noncoding sequences have been removed. The new idea behind DNA cryptography is to exploit this to encrypt a message. The message is encoded in the sequence of bases in the DNA (A for 00, C for 01, G for 10, T for 11, for example) and then processed. The resulting protein is then made public. The key, which is kept private, is the information necessary to reassemble the DNA from the protein, such as the position of the noncoding regions (abstract)."
Quantum Mechanics is a lovely introduction to Hilbert Spaces!
-- Overheard at last year's Archimedeans' Garden Party