Low copy number (LCN) DNA = Ramsey's far from cleared

Discussion in 'JonBenet Ramsey' started by cynic, Jul 13, 2008.

  1. cynic

    cynic Active Member

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    Because of the small amount of DNA obtained from JBR and the techniques used , it's far more likely that JBR simply deposited DNA that she picked up (the same that was found under her fingernails) to her panties and leggings.
    LCN DNA is far better used to include rather than exclude suspects.
    Below are some excerpts from http://www.denverda.org/DNA_Documents/LCN DNA Profiling.pdf
    that highlight some of issues involving LCN DNA ("touch DNA")

    Transfer of DNA by individuals unassociated with the crime before the crime event itself is defined as adventitious transfer.
    When a DNA profile does not match the suspect, the following possibilities apply:

    a) The suspect is innocent and the perpetrator profile has been visualized.
    b) Cells have been transferred by an innocent individual before the crime (perpetrator has not shed cells) – ‘adventitious transfer’.
    c) Cells have been transferred by an investigator after the crime event (perpetrator has not shed cells) – ‘contamination’.

    Because the DNA test is very sensitive, it is not unexpected to find mixtures. If the potential origins of DNA profiles cannot be identified, it does not necessarily follow that they are relevant to this case, since transfer of cells can occur as a result of casual contact.
    Effectively, the strength of the LCN DNA evidence is decreased compared to conventional DNA analysis. This inevitably arises from uncertainties relating to the method of transfer of DNA to a surface and uncertainties relating to when the DNA was transferred. It is emphasized that the relevance of the DNA evidence in a case can only be assessed by a concurrent consideration of all the non-DNA evidence.
     
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  3. Grainne Dhu

    Grainne Dhu New Member

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    According to the Associated Press, LCN DNA testing was not done. They scraped the leggings and amassed enough cells to use the regular DNA test. The reason the leggings were sent to that particular lab is because they are equipped to run LCN DNA but it turned out not to be necessary.

    I think it's clear that they need to send at least some of the other evidence to be tested, if not all of it.
     
  4. Ames

    Ames New Member

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    I second that!!!
     
  5. Solace

    Solace New Member

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    Cynic, correct me if I am wrong, but I do not believe the DNA under her nails and the underwear matched. We would have heard that a long time ago and the news today would be old. I do not believe the unsourced DNA under her fingernails of both hands is a match to the 9 degraded markers in her underwear.
     
  6. Solace

    Solace New Member

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    Before they do any of that, they should have Lacy tested.
     
  7. LI_Mom

    LI_Mom New Member

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    LOL!!!

    http://jonbenetramsey.pbwiki.com/The Body#DNAEvidence


    I see they never even took samples of ALL the people at the White's party.

    How can they be sure the male dna came from one of the young boys there....

    transferred innocently (or not) and then JB transferred the dna from her own hand to the couple of things they bothered to test.
     
  8. Solace

    Solace New Member

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    Exactly. Hi LI Mom.
     
  9. cynic

    cynic Active Member

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    Many press reports have stated that "touch DNA" cleared the Ramsey's. Touch DNA is LCN.
    Do you have a source?
     
  10. Solace

    Solace New Member

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    Cynic,

    There is no proof that the unsourced DNA under her fingernails matches the DNA in her underwear. The DNA in the underwear is degraded and has less than the required 13 markers for a complete and ABSOLUTE match. So a good portion of the markers are going to match, it is that very small percentage that sets us all apart. This DNA touch test means nothing as far as exonerating anyone. They have degraded DNA that they say matches DNA on another part of the clothing.

    They, as usual, say a lot of things.

    One of the last reports had a reporter calling them the "Benets". If a reportere can't even get the name right, what is one reporting on it for. It is unreal.
     
  11. LI_Mom

    LI_Mom New Member

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    Hiya Solace. :)


    If I DIDN'T want to solve a crime, I'd proceed exactly the way they did/do in the Ramsey case.

    It's laughable AND pitiful that anyone could ever dream that this half-azzed investigation is moving them any closer to any TRUTHFUL answers.
     
  12. Jayce

    Jayce New Member

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    They were able to get enough markers to enter into CODIS. They don't have enough for an ABSOLUTE match, but they have more than enough to be extremely confident.
    Wrong. You are confusing the fact that we all have a very high percentage of the same genes with the erroneous assumption that we therefore have a good number of the same genetic markers. The odds of two people, randomly chosen, even sharing a few of the same genetic markers isn't very good. The odds of all LOCI (I think they got 10) from the DNA in the underwear matching all the LOCI from the newly found DNA is astronomical. It isn't a for sure match, but its pretty close.
    It goes a long way to exonerating the Ramseys. The so-called "degraded" DNA, especially with advances in technology, is still very useful.
     
  13. Chrishope

    Chrishope New Member

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    It goes a long way to exonerating the Ramseys. The so-called "degraded" DNA, especially with advances in technology, is still very useful.

    How do you figure it exonerates anybody?
     
  14. Ames

    Ames New Member

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    That's correct Solace...I don't know why I keep reading posts for posters that think that the two matched. There was no DNA under JB's nails that implicated anybody, that's how we know that she was unconscious while being strangled...she would have had the killer's DNA under her nails...and she didn't. And her arms were tied SO FAR APART and in front, that she still could have scratched her attacker...if she had of been conscious during the strangulation. I speak from experience...as you know...as to JB scratching her attacker if she had of been able to.
     
  15. Jayce

    Jayce New Member

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    I didn't say that it exonerates anyone. I said it "goes a long way to exonerating". Why? Because finding the same unidentifed man's DNA in three different locations on two different articles of clothing, in areas where the killer was sure to have had contact with, is compelling evidence that there was an intruder.
     
  16. Grainne Dhu

    Grainne Dhu New Member

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    Yes; I found the AP report here:

    http://seattlepi.nwsource.com/national/1110ap_jonbenet_ramsey_dna.html

    I don't think it requires a registration for reading articles, only for using their forums--but it's been a long time, they may require registration. If they do, it is free.

    The article states: "While the amount of DNA they found was much less than would appear in a stain, there was enough that it was processed in the routine way for analysis, Williamson said. (In other cases, so-called "low copy number DNA" has to be processed in a different way)."

    Malcolm Ritter, the author of the article, is subtitled "Science Writer for the AP."

    Mary Lacy stated that she originally sent the longjohns in for testing after she attended a presentation about "touch DNA." The lab she sent the longjohns to is set up to do LCN DNA but it turned out not to be necessary.
     
  17. LI_Mom

    LI_Mom New Member

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    You know.... if they keep doing these INCOMPLETE dna tests on items that started out with TINY amounts of evidence, it won't be long before they have NO SAMPLE left if the case ever gets to trial.

    Any decent defense attorney will demand to run his own independent tests to verify the prosecution's findings.
     
  18. Ames

    Ames New Member

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    Maybe that's the whole idea.
     
  19. Chrishope

    Chrishope New Member

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    Hmm, well maybe we have different conceptions of exoneration. To me evidence either exonerates someone, or it doesn't. IMO, this doesn't.

    It's not compelling evidence of an intruder, it merely means there is dna in 3 palces on two articles of clothing. We don't know how it got there. We don't know that JBR didn't transfer it there herself.
     
  20. LI_Mom

    LI_Mom New Member

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    I wouldn't put it past them (Ramseys & their supporters), that's for sure.
     
  21. Ames

    Ames New Member

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    Why were the long johns and panties the only things tested anyway? DNA from an unknown male in those places, doesn't necessarily make that person the killer. If Mary Lacy is serious about clearing the Rams...she needs to test a heck alot of other things. I believe that the blanket that JB was wrapped in like a "papoose"...for sure would have Touch DNA...along with the broken paint handle and garotte...just to name a few. Why weren't these things tested? And if they were...why weren't we told about it, and the results released?
     

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