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  1. #1
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    Exclamation Obstructions to matching the missing and UID -Q&A's/FAQ's only please!

    So what keeps us from matching the missing and unidentified - in addition to not being in a database?

    Let's please try and keep this a Q&A' thread only- close to a non discussion thread as we can, please.

    I'm hoping Carlk' will give us a laymans example of:

    Dentals:
    How do they mistakingly rule out?

    DNA:
    How does Mitochondrial versus Nuclear compare when it is available in Codis?

    -What if the missing person only has Nuclear available and no mitochondrial available? What obstacles will ME have?


    Any other FAQ's for uid's and the missing please add.

    thanks,

    Cubby

  2. #2
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    I am cross-referencing my comment from another thread to here for general reference.

    I was pointing out as concisely as I could why it is that if they have only nuclear DNA on a missing person and only mitochondrial DNA on the UID (or vice versa), you still won't be able to make a valid comparison.

    The cases of Mindi Chambers and DoeNet Case 72UFTX are an example of two cases where authorities believe there is a match, but they cannot prove it because they only have mtDNA from the UID, and only nucDNA from paternal relatives. No maternal relatives are available to resolve this likely match.

    http://doenetwork.org/cases/72uftx.html
    http://www.charleyproject.org/cases/...ers_mindi.html

    Quote Originally Posted by CarlK90245 View Post
    Quote Originally Posted by Cubby View Post
    ... maybe CarlK can chime in, but I don't think nuclear and mitochondrial dna can be compared against each other. Carl?

    tia
    You are right, or at least that's the way I understand it. Nuclear DNA is entirely different from mitochondrial DNA, and you cannot compare the two against each other.

    The mitochondrion is a sub-microscopic organism that lives within a cell-wall, but outside of the cell's nucleus. It is not an inherent part of the person in whose cells it resides, and therefore, it has an entirely different DNA sequence from the DNA within the nucleus.

    Since sperm cells do not contain mitochondrial DNA and egg cells do, Mitochondrial DNA passes unchanged from mother to child, and it remains unchanged as the cells divide to form a human being.

    If there is a mtDNA match between two individuals, it doesn't necessarily mean that they have the same mother, or even the same maternal grandmother. It only means that the ancestral chain that connects the two persons to each other consists entirely of female ancestors.

    This connection may go five generations up your family tree and six generations down another branch (i.e., fifth cousins, six times removed), and if each link in that chain consists of female ancestors, the two persons will have identical mtDNA.

  3. #3
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    Thanks Carl, I did not mean to put you on the spot. I thought this might be a good area for FAQ's regarding obstacles such as DNA and dentals when it comes to official matches for the unidentfied.

    TY!

  4. #4
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    From a separate thread, addressed here to avoid going off-topic.

    Quote Originally Posted by Julessleuther View Post
    Wow Carl, thank you for the information. Don't want to get off topic, but DNA is so confusing! Makes me wonder if some of the DNA entered for many UID is of one type, and DNA for missing is of another kind and therefore not able to be matched. Does that happen often?
    I was told by Hal Brown (from the Delaware State MedEx Office) that Family Reference Samples (FRS) are processed entirely by an automated system, and any nucDNA samples taken from maternal relatives are also processed for mtDNA.

    However, if only paternal relatives are available (e.g., Mindi Chambers), no mtDNA profile can be developed.

    Also, if the unidentified body is too badly degraded, they might not be able to extract nucDNA even if they are able to extract mtDNA. As I understand it, mtDNA is more resistant to degradation than nucDNA.

    Also, although it is often denied that there are known instances of false negatives in CODIS, I know of one instance where DNA was available in CODIS for both the MP and the UID, and a hit was not triggered.

    Dawn Renee Higdon of Ridgecrest CA went missing in Aug'88 and her skeletal remains were found in Jul'90 in San Bernadino County.

    Here is the link to info regarding Dawn (no info is available about the previously unidentified remains)
    http://forthelost.wordpress.com/2010...nty-two-years/

    These cases remained unmatched despite the existence of a single FRS from one of Dawn's relatives, and a DNA profile for the UID in CODIS. (I'm not sure whether they were nucDNA or mtDNA, or whether the single relative was maternal or paternal). It was only after additional relatives submitted FRS samples that a feature in CODIS called "Pedigree Tree" evaluated the multiple samples collectively and then was able to flag the match to the UID case.

  5. #5
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    Here is some additional info from David Van Norman in response to two questions that I posed to him. My questions were:

    (1) Is it a correct assumption that If only a mtDNA sample is available for a missing person, and only a nucDNA sample was available for the unidentified decedent, CODIS would not be able to identify the match?

    (2) If only one sample of familial nucDNA is available to compare to the nucDNA of the UID, is there a significant risk of a false negative?

    He responded as follows:
    Answer #1: Correct – nucDNA = apples and mtDNA = oranges! Or nucDNA is BluRay and mtDNA is VHS. The problem is California’s lab philosophy to develop nucDNA first (because it gives a higher confidence chance of a match and “positive” ID), whereas other labs go for mtDNA first.

    Answer #2: Correct – In fact if there is only one familial sample submitted for a missing case, so I am told by the folks at UNT, CODIS will not even bother comparing that profile against UHR due to the sheer volume of matches it will elicit. They require two or more to search. Sadly, they aren’t advertising that so cops who watch too much TV stupidly continue to submit just one family member when many are available. I had an LAPD detective tell me that they didn’t have to sample the mother of a missing man’s child since she contributed nothing to his DNA. Apparently he hadn’t heard about exclusionary samples. (PS – That child’s DNA was subsequently matched by a cold DNA hit to skeletal remains found after a fire near Griffith Park).

  6. #6
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    I was just going to ask this same question.What if there is no DNA for the missing person.So her sister put in CODIS her DNA for a match with a Jane Doe and her missing sister.I believe they would have gotten mtDNA from the sister right?My question please is will the Unidentified Jane Doe with only nucDNA show up a match with the sisters mtDNA as a CODIS match?I hope I explained that right.I'm sorry.
    ALL EVIL NEEDS TO SUCCEED IS FOR GOOD PEOPLE TO DO NOTHING!!!!

  7. #7
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    Quote Originally Posted by Ms Suzanne View Post
    What if there is no DNA for the missing person. So her sister put in CODIS her DNA for a match with a Jane Doe and her missing sister. I believe they would have gotten mtDNA from the sister right?
    The standard practice is to get both nucDNA and mtDNA from the Family Reference Sample (FRS) submitted by the relative. However, with unidentified remains, both DNA types aren't always obtained. As VanNorman indicated above, different jurisdictions have different priorities.

    If the sister provides the only FRS for comparison, then a mtDNA comparison would be possible (assuming that she and the missing person have the same mother). However, according to VanNorman, CODIS requires more than one relative to submit DNA for the more definitive nucDNA comparison.

    However, a mtDNA hit only means that the two people compared are connected in the family tree by a continuous chain of female relatives. That connection may span over multiple generations, up one branch of the family tree and down another, and may involve distant relatives that the two people never knew.

    a nucDNA hit is more definitive, but you need more than one FRS to achieve statistically significant results.

    Quote Originally Posted by Ms Suzanne View Post
    My question please is will the Unidentified Jane Doe with only nucDNA show up a match with the sisters mtDNA as a CODIS match?
    No. Mitochondrial DNA (mtDNA) is entirely different from Nuclear DNA (nucDNA). mtDNA comes from sub-microscopic organisms within our cells called mitochondria. A mitochondrion is not an inherent part of the person in which it resides, and therefore, it has a completely different DNA sequence from the nucDNA that uniquely defines each person.

  8. #8
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    I'm stumbling through this and it is all new to me so please excuse my ignorance.

    Are you saying that NucDNA comes from the father or the males in the family?
    A parole review date is set for July 21, 2012 for Fred Howard Coffey.

    Coffey was convicted of the murder of 10 yr old Amanda Marie Ray, NC. He admitted to molesting 300 children.

    Please write a letter on behalf of Amanda.

    Suspect in the murders of:
    5 yr old Neely Smith, NC
    14 yr old Kathy Lynn Beatty, MD
    8 yr old Travis Shane King, VA

    Possibly connected to the disappearances of:
    14 Yr old Tracy Anne King, PA
    11 yr old Sheila and 13 yr old Katherine Lyons, MD
    15 yr old Carolyn Majane, NJ



    Write to:
    Chairman Charles L. Mann Sr.
    NC Post Release Supervision & Parole Commission
    P.O. Box 29540
    Raleigh, NC 27626-0540
    RE: Fred Howard Coffey, DOC# 0081135
    or send an email to parole@doc.state.nc.us
    http://justice4amanda.tripod.com/

  9. #9
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    Quote Originally Posted by JeannieC View Post
    I'm stumbling through this and it is all new to me so please excuse my ignorance.

    Are you saying that NucDNA comes from the father or the males in the family?
    No - nucDNA comes from both the father and the mother. Our nucDNA is an approximate 50-50 mix of the nucDNA from both parents.

    Mitochondria are also found in most of the cells of both males and females, including a female's egg cells. But they are virtually absent in a male's sperm cells. Consequently, mitochondria are passed to us only from our mothers, and the mtDNA taken from the mitochondria is not a 50-50 mix from both parents. It's a 100% duplicate of the mtDNA from the mother.

    I had said earlier that a mitochondrion is not an inherent part of the person in which it resides. To use an analogy, a mitochondrion is to the cell in which it resides, as a leech is to the whale on which it resides. A mitochondrion's DNA is different from the nuclear DNA of the host, just as a leech's nucDNA is different from the nucDNA of the whale.
    Last edited by CarlK90245; 09-01-2011 at 12:49 AM.

  10. #10
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    I have a question if someone knows the answer to.If you have an adult Unidentified male that has Partial (6) STR's and full mito profile recovered from remains and a little boy with only mito DNA on him.Can they find a relationship between them?I hope I said that right.
    ALL EVIL NEEDS TO SUCCEED IS FOR GOOD PEOPLE TO DO NOTHING!!!!


  11. #11
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    What kind of relationship? Do you mean if they're the same person? Since both have a mitochondrial DNA profile available they can be compared.

    If you're asking about a familial relationship they might be able to match the boy to adult males that he's maternally related to, that is, his brothers, sons of his maternal grandmother, but mitochondrial DNA can't be used to determine the adult male is the boy's father, for example.

  12. #12
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    Quote Originally Posted by Ms Suzanne View Post
    I have a question if someone knows the answer to.If you have an adult Unidentified male that has Partial (6) STR's and full mito profile recovered from remains and a little boy with only mito DNA on him.Can they find a relationship between them?I hope I said that right.
    It depends on what their actual relationship is to each other. If they are brothers with a common mother, the mtDNA comparison will result positive. But it won't prove what their relationship is to each other. It only shows that they are linked by one or more female ancestors along the maternal line of their family trees. That common female ancestor could be a mother, maternal grandmother, or several generations above that.

    If the relationship is father/son, the mtDNA test will result negative.

    The partial STR is irrelevant in your hypothetical because they don't have nucDNA on the boy. Assuming that they had nucDNA on the boy, they could do a manual comparison, but CODIS requires a full 13 alleles in the STR profile, so they wouldn't be able to put the UID male in CODIS.
    Last edited by CarlK90245; 09-04-2011 at 02:36 PM.

  13. #13
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    Thank you.I was thinking Father and son.
    ALL EVIL NEEDS TO SUCCEED IS FOR GOOD PEOPLE TO DO NOTHING!!!!

  14. #14
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    One additional point, Ms Suzanne-IIRC Paternal/Y DNA mutates one in about 500. So it is possible for a boy to be related to a man, but the paternal DNA might indicate otherwise. Paternal DNA needs to be, usually, corroborated by a family history.

    http://dna.ancestry.com/learnMorePaternal.aspx
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  15. #15
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    kpdx is offline Jane Doe was discovered Aug. 14, 1977 outside of Everett WA
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    Quote Originally Posted by CarlK90245 View Post
    The cases of Mindi Chambers and DoeNet Case 72UFTX are an example of two cases where authorities believe there is a match, but they cannot prove it because they only have mtDNA from the UID, and only nucDNA from paternal relatives. No maternal relatives are available to resolve this likely match.

    http://doenetwork.org/cases/72uftx.html
    http://www.charleyproject.org/cases/...ers_mindi.html
    Thanks so much for this, CarlK, it was a very elegant, concise demystification of an otherwise complicated issue.

    In the case of Mindi, who looks to be an obvious match, can they not compare dentals..especially since Mindi would of at a min. had records from orthodontist?

    Another question that comes up consistently (and has resulted in rule outs) is height. Typically, UID's have a range provided (as in the case of the TX Jane) whereas MP have an exact number. I'll address this to the broader forum as I know we have lots of experts around

    1st Q: As I understand it, height is based on comparing measurements of specific bones with established height chart. Is this standard practice, or does it vary based on decomp? What is the general practice of ME when determining height?

    2nd Q: A recent doctor visit identified that my own medical records had me at a shorter height than I am (in my 30s, so obviously not a result of a growth spurt). I always assume a margin of error in a MP's height...but how does LE treat it? Are heights self reported by family, or are they based on medical records? Are medical records accessible to LE when investigating MP? Over the years, I have seen rule outs based on a difference of a few inches when otherwise the match looks good....

    Thanks!
    Last edited by kpdx; 10-06-2011 at 11:07 PM. Reason: spell correction
    'Nothing clears up a case so much as stating it to another person.'

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