A couple of articles for you.
Persistence of spermatozoa and prostatic acid phosphatase in specimens from deceased individuals during varied postmortem intervals. - PubMed - NCBI
The recovery of seminal components and DNA from the vagina of a homicide victim 34 days postmortem. - PubMed - NCBI
The second is a case study from Maine where they were able to recover both seminal components and DNA from a female 34 days postmortem.
and lastly this one:
[The forensic expertise of cadavers of females suspected to be victims of sexually motivated homicide]. - PubMed - NCBI
It's why DNA has become an intriguing field. Even with touch DNA there is conflict on how long that DNA lasts. Let's say you're being tried for a murder, your DNA was found at the crime scene. You could argue, and win, that your DNA was left there long before the crime occurred, possibly even years earlier, because there is no "set" time for the degradation of DNA. In a corpse, on the soil, under corn leaves, there is a difference in the rate of degradation of the corpse itself, but interior areas, for lack of a better term, hold on to things like seminal and epithelial DNA. The putrification process makes "pockets" for preservation of DNA, much like teeth (in older cadavers) and the inner ear (in less degraded cadavers).
I read the abstracts you cited (would love to be able to read the original articles). Not one cited frequency.
Sure, you may be able to find perp DNA in an individual case after a month of decomp, but not every time, and that is my point, that it is a crap shoot as to whether or not usable perp DNA will be found on or in MT, especially male gametocyte DNA! One black swan does not mean that I will see one every time I go fishing!
I totally agree with the final line of the later article that encourages looking for spermatazoa even at 1.5 to 5 months post-mortem, because they MAY be found if you look for them. Never give up, never surrender. Leave no tern unstoned. No argument on that point at all. The point of the article is that you should look, because while it's unlikely YOU might just luck out and find something. "...there's gotta be a pony in here somewhere"
Also, the 34 day single case outlier you cite was found in Maine. In a Maine winter, I completely agree that DNA, and the rest of the body, may keep for months, it's a deep freeze! What were the environmental conditions associated with that corpse's decomp? I think you might be able to even keep frozen embryos in a river in Main in January. Maybe that's Pluto, I get confused when I drink.
With MT we are talking about an Iowa Summer. I've been there, sweated that, and embarrised the school administration into buying additional window AC units for the main lecture hall. Iowa (eventually) gets hot in the summer. In July of '83 It was 102 in the afternoon- destroyed the corn crop.
You have said in several posts that DNA is somehow more resistant from degradation, by the 1000's of bacterial species associated with decomp, than other bio-molecules. Again, I ask you to please document this. DNA is made up of the same building blocks as the rest of the body, ALL of which bacteria were made to breakdown and metabolize. It's a great circle of life thing.
In your final paragraph, you conflate perp and victim DNA. I TOTALLY agree that viable VICTIM DNA can be obtained from the interior of molars or the inner ear bones of a skull found on a dog walk, perhaps years later (Like the 500+ year DNA Half-Life you have previously mentioned)
But I defy you, or anyone else, to find perp DNA in either location unless there was an icepick and some really kinky sex involved!
I do grasp your point that there are pockets that may be formed that could hold male gametocyte DNA (like the cul-de-sac/pouch of Douglas). But the problem is that with an advanced enough state of decomp, you can't swab a vagina if there isn't one left to swab. And as far as touch DNA is concerned, that would likely be the first to go, with the effect of rain and decomp.
There is a much better chance that CR's DNA will be found on MT's clothes, but bacteria and mold and fungi can also degrade that, with time and summer heat.
I agree that DNA is a robust molecule, and there is a lot of it, even in a single cell, but ALL things degrade, entropy is harsh in that way.
