Biocodicology - A Deeper Dive

[MichelleL11]

I was curious as to how fast DNA degrades. I found the following article:



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To what extent can we expect that human or animal DNA from the time of the manuscript's construction has survived to the present day such that there are long enough strands of DNA even if incomplete that they would be suitable for sequencing? (I assume that even if strands are incomplete if they are long enough DNA sequences generated from separate strands can be combined to generate a full sequence.)



Is "touch" DNA likely to degrade much much faster?

Hi, Mark:

Thanks for that link to the paper reporting a generally assumed half-life of DNA at 521 years.  It appears this DNA had been "stored" in the bones of dinosaurs that had been underground with very similar humidity (groundwater) conditions.  So with those assumptions in place, that is how long it took for half the DNA to decay.  Estimates for other "rates of decay" will need to take in to account how the storage conditions vary from the conditions underlying their calculations.  One interesting conclusion is that the best temperature appears to be -5 degrees C (23 degrees F) --- and all libraries are definitely warmer than that (at least I hope so for the poor librarians).

I don't know very much about touch DNA, since that is a very "forensic" branch of these kinds of analyses which is different than my work.  But a little bit of poking around found the following possible publications:

1. You are not allowed to view links. Register or Login to view., Alketbi 
2. You are not allowed to view links. Register or Login to view., MIT Lincoln Laboratory
3. You are not allowed to view links. Register or Login to view., Sharma
4. You are not allowed to view links. Register or Login to view., Menchhoff et al.

I thought this last one may be the closest you're going to get because it involves stored latent fingerprint cards -- so the amount of time involved could be significantly longer than what the other more general articles might consider -- but obviously still a much shorter time period than what would be involved with the VM.

There is at least one publication about residue from touch in manuscripts that I haven't looked closely at, but could also be useful in pursuing your questions (I think some of these might have been referred to in some articles that have been linked in this string) and also here is a high level article that includes references to the article I just reviewed and one I think I'll be reviewing closely but probably not next (maybe the one after that):

1. You are not allowed to view links. Register or Login to view., Rudy
2. You are not allowed to view links. Register or Login to view., Gibbons

Hope these articles help clarify the issues.