No, I knew what an SNP was. As stated, it's a single nucleotide polymorphism-- A change of a single base pair in a gene coding region that is not 100% conserved between humans, and is part of the information in a person's genome that makes them unique. (The unique constellation of these polymorphisms is what sets an individual human apart from other humans, genetically.) I think it more likely that I just didnt explain well enough, and caused confusion. (That's a problem I often have.)
I was meaning, that for each unique sequence, you have around 50 to 100 beads that become semiconductive after the unique DNA sequence docks. (So if you have 100 possible variants on a coding region you are assaying against, and 100 beads for each, that's 10,000 beads. It is unlikely that you will have 100% successful docking of the DNA with your assay chip, which is why you need redundant beads per unique conformation. You can overcome uncertainty that your "hit" or "miss" is random this way.) One way to accomplish this is to use the DNA molecule as the gate layer of a hybrid organic diode, where only a specifically coded DNA sequence can attach, and form this diode.
It has been known since at least 1999 that DNA is semiconducting.
http://physicsworld.com/cws/article/news/1999/apr/01/dna-is-a-semiconductorAssembling a purely electronic detector is well within the realm of possibility.
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Not a biotech engineer-- just an old IT guy-- but if I were, and had access to such toys, I would adapt upper atmospheric microbes into high temperature extremophiles tailored for life in a very high pH, nitrogen depleted, and chemically arid (eg, surrounded by strongly hygroscopic, nearly anhydrous acids in both vapor and droplet forms) conditions, that is able to synthesize appreciable quantities of aramid plastic, using a sulphur respiration cycle.
It's the kind of thing that I feel is needed to free Venus from its runaway greenhouse effect.
Many useful mechanisms could be lifted from existing terrestrial microbes. Producing a viable biochemical pathway to synthesize this heavy (and energy dense) polymer would be a feat in and of itself, and getting the many different mechanisms from very disparate places to work nicely in the resulting custom microbe would be even harder.
Probably would not succeed, but it would still be fun.