"David Lubkin" <lubkin@unreasonable.com> writes:
> Variant 2: Commercial genetic-engineering firms use PGP to encipher a
> message, which they place in the introns of modified products they sell, as
> proof of the authenticity of the product. Or, they hide a message, perhaps
> including a serial number, as a way of detecting piracy.
Certification and signatures: you want to make sure your DNA has not mutated or been tampered with.
> Variant 3: Or spies use it, to transfer information. The secret plans to
> the new weapon are in the E. coli in the intestinal tract of the agent.
> Or in the placement of phosphorus in the third rib of a puppy being shipped
> to Riyadh.
Or in the next epidemic of the common cold. Unfortunately these methods are rather slow compared to just piping some encrypted and steganographed information along with dirty pictures to Riyadh ("But boss, we just use the pictures to hide the information, not for looking at them! Promise!")
> Question -- What biological structures or biochemical patterns can we alter
> today, or very soon, with a fine enough granularity to fit a lengthy message
> and long-term stability? Which can be altered in vivo, and which can only
> be used on corpses?
DNA is likely easiest, with a capacity for at least megabyte messages.
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