Remember that Screen Capture of the DNA lab report shown on the 48 Hours program? It wasn't clear, but here's what I got out of it:LAB CLASS XX???-2136(?)-4153(?) SECTION: DNA TESTING
AGENCY(?) NAME – CD0878136 – F2 ACBLDER(?)
EXTRACTED(?) BY: blacked out EXTRACTION DATE: 123196(?)
ABSTRACT(X) AFA(?) ?/? ???
RAMSEY, PATSY W/F
RAMSEY, JOHN W/M
RAMSEY, JONBENET W/F
Two lines BLACKED OUT
DATE COMPLETED/JANUARY 13, 1997
EXTRACT(?) DESCRIPTION
#5A,5B# (?) Bloodstains from shirt
#7 Bloodstains from panties
#14B Bloodstain ????? from JonBenet Ramsey
#14J DNA? Or Swab? with Saliva????
#14L, #14M Right and Left hand fingernails from JonBenet Ramsey
#15A, #15B Samples from tape
Bloodstains from white blanket
#17A, #17C Bloodstains from nightgown??
#13A, #13B Semen ??? stain from black blanket
Bloodstain Standard from John Andrew Ramsey
_________________________________________________________________(fold in page??)
LABORATORY REPORT
BB AB BB AA AC 24,26
??????? Section Testing WB
BB AB BB AA AC 24,26
WB WB
BB AB BB AA AC 24,26
WA WB WB W18 (?)
THE DNA PROFILES DEVELOPED FROM EXHIBITS #5A, 5B, AND 17C MATCHED THE PROFILE FROM JONBENET RAMSEY.
(the left side of the page seems to be cut off and starts with)
FED FROM EXHIBITS #7, 14L AND 14M REVEALED A MIX-
(left side cut off) COMPONENT MATCHED JONBENET RAMSEY. IF THE MINOR
(left side cut off) 5 #7, 14L AND 14M WERE CONTRIBUTED BY A SINGLE
(JOHN is cut off) ANDREW RAMSEY, MELINDA RAMSEY, JOHN B. RAMSEY, JEFF RAMSEY (blacked out)
(cut off??) EXCLUDED AS A SOURCE OF THE DNA ANALYZED.
At that point the names go off the screen, but we can reasonably infer that the rest of the listing is of BLOODSTAIN STANDARD FROM John, Patsy, Burke and Melinda, plus John's brother Jeff and another named individual or two or three who have been censored out of the broadcast copy
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THIS is CLEAR EVIDENCE that the FIRST tests "completed Jan 13, 1997" used an identification kit that profiled only FIVE MARKERS and were identified as:
1. BB - means one parent contributed B and one contributed A at this location in the DNA
2. AB - means one parent contributed A and one contributed B at this location in the DNA
3. BB - means one parent contributed B and the other B at this location
4. AA - means one parent contributed A and the other A at this location
5. AC - means one parent contributed A and the other C at this location
These 5 "identifications" are repeated three times in this report and it is revealed that they identify JonBenét's DNA, which matched "exhibits" #5A & #5B, "bloodstains from shirt" and #17C, "bloodstains from nightgown".
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Say we have a VERY poor sample of the foreign componenet of the mixed DNA sample in this case where there is only ONE marker and that marker is in "position" 1. (See above: JonBenét's is identified as "BB").
Say the foreign componenet of the mixed DNA identifies "position" 1 as AA.
Then we get a sample of DNA from a suspect and his "position" 1 marker is AC. We know FROM JUST THAT ONE MARKER that he is NOT the contributor of the foreign DNA because his "postion" 1 marker is not AA. HE IS ELIMINATED on the basis of just that ONE marker! No matter how "minute", "degraded", "incomplete", less than perfect the DNA profile, we can eliminate EVERYONE whose DNA does NOT come up as AA in the "postion" 1 marker.
Okay, so let's say we have a slightly better sample with TWO MARKERS. "Position" 1 is AA and "position" 2 is BB. (Looking at JonBenét's DNA, her "position" 1 is BB and her "position" 2 is AB.)
Say we get a suspect and his DNA shows "position" 1 is AA, but his "position" 2 is AB. We can eliminate him and EVERYONE whose "position" 1 is NOT AA and/or "position" 2 is NOT AB. That's a LOT of eliminating with ONLY TWO markers.
With THREE markers, EVEN more discrimination is determined. There are only FIVE to begin with.
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By itself, that polymarker identity kit doesn't have as much information as we'd like though because it's not too unusual for two different people to have AA in "position" 1. If you have a piece of evidence with DNA that's AA at "position" 1 and a known person that's AA at the same location, that will happen fairly often just by chance.
The polymarker test uses five locations that are identified like that and provides a fair amount of information, exponentially increasing discriminatory information with the addition of each marker pulled out of the DNA profiling process.
DQ ALPHA
THEN there's the DQ ALPHA, identified in JonBenét as type 24,26 in the screen capture.
DQ Alpha is identified as numerical designations. There are 21 combinations. You might get a 1.1 from one parent and a 1.1 from another parent. Or you might get a 4 from each of your parents and be a 4, 4. Or you might get a 1.1 from one parent and a 4 from the other, in which case you'd be a 1.1, 4.
Each one of these that have a number designation in the DNA is different because there's a difference in the sequence of the base pairs at that DQ Alpha location. This offers even more discrimination than just the identities in 5 locations described above.
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RFLP v PCR
When there is a larger DNA sample in good condition, RFLP testing is usual. When there is a smaller sample or one that is not in good condition, PCR testing is the usual. The RFLP test is much more powerful in discriminating between one person and the next. Any particular RFLP banding pattern is not a common event.
If they can't do an RFLP test and they do a PCR test, they are not getting the same amount of information, but it's still useful. It allows them to exclude someone as being a contributor and it allows them to include one as being a possible contributor. Then they can put a frequency to that ==>> how often might you see this combination of genetic types. If that number is one in a million, you wouldn't see that combination very often.
We were told that in the Ramsey case the testing was PCR, DS180
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DEGRADATION:
In the context of DNA, it means that the DNA molecule is broken down.
Let's say that the DNA molecule is equivalent to a very long piece of thread unwound from a spool, that would be one DNA molecule from one chromosome.
If I took a pair of scissors and cut that thread in 40 different places that might be the equivalent to the DNA being slightly degraded, randomly broken in 40 different locations. It is no longer all in one piece.
So if I took that same thread and I cut it at 1,000 locations, it would be in a lot smaller pieces and that would be the eqivalent of being more degraded than if I cut it in 40 locations.
Degradation is something the labs see all the time. If I had somebody draw my blood and had the DNA extracted from it right then, the result would be DNA that's in very good condition, but might be broken up a little bit just due to the process of handling it.
If you have human cells left at a crime scene and those cells are not in the body any longer, they are subjected to whatever environmental factors at that crime scene ==>> sunlight, heat or a number of other factors. All of the things that affect the cells of a deceased person will eventually affect the DNA and it will gradually degrade. Depending on where it is and what conditions it's under, it may degrade more, or it may degrade less.
They are still able to test degraded DNA to determine the information described and degradation won't change somebody's type to be something other than what it started out to be. So you either have
- all the information that's there in the DNA,
- lose SOME of it, or
- lose all of it.
SUBSTRATE CONTROL
is when they take an area of the cloth that is not obviously stained, but adjacent to the stained area, or, if they were lifting a stain from a surface, they would lift the stain up and then take another lift from an area adjacent to the stain that was not apparently stained. They would hope for no detectable result from the substrate control.
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RE: The FIRST DNA TESTS
RE: The FIRST DNA TESTS
