UK Justice Forum 🇬🇧
Disappeared and Abducted Children and Young Adults => Madeleine McCann (3) disappeared from her parent's holiday apartment at Ocean Club, Praia da Luz, Portugal on 3 May 2007. No trace of her has ever been found. => Topic started by: debunker on April 24, 2013, 07:33:09 PM
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Any takers?
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Any takers?
Seems to be a deafening silence when confronted with facts.
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There are so many dog threads that I get lost.
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There are so many dog threads that I get lost.
This isn't dogs; it's the science bit.
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There are so many dog threads that I get lost.
This isn't dogs; it's the science bit.
I think I have read your explanation before DB, and although I got the gist of it, it proved too technical in parts for me to completely comprehend. (that's my fault not yours btw).
If it's possible to explain in 'Janet and John' language - then I would be most interested in reading it.
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The floor is your's DB...
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
you seem to use 'we' an awful lot
is that the Royal we?
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I'd try and get my money back from that 2 day NLP programme you attended
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I'd try and get my money back from that 2 day NLP programme you attended
And petty sniping progresses the debate how ?
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
you seem to use 'we' an awful lot
is that the Royal we?
Not at all
... just a subconcious longing for companionship, perhaps
It can be a very lonely on this board, at times, when you do not march to the required McCann drum 8)-)))
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
you seem to use 'we' an awful lot
is that the Royal we?
No. It is called the 'inclusive we'- seeking to include a group of people in a proposed action as in 'shall we go to the pub?' Simple English usage. Silly point-scoring on your part.
I will develop this thread today.
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
you seem to use 'we' an awful lot
is that the Royal we?
Not at all
... just a subconcious longing for companionship, perhaps
It can be a very lonely on this board, at times, when you do not march to the required McCann drum 8)-)))
Silly contentious, fact avoiding point scoring from you as per usual.
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If we take a sample of tissue or blood or other substancefrom a person or a crime scene, and this is found to have complete unbroken strands of DNA in it, then ordinary DNA analysis can be done.
This is carried out by a process that strips the DNA strands and allows scientists to identify particular short lengths of DNA with a recognisable pattern of complex chemical elements attached in certain places.
It has been shown that these chosen areas (a different number and different locations in different jurisdictions) contain sufficient variety of structure to make rational decisions about whether different samples do in fact match to a level of probability suitable to make a scientifically and forensically valid conclusion.
This complexity is because these twenty sites (In current usage) have a variety of chemical structures (called here 'markers' (elsewhere alleles) which are associated with these particular locations. Each area has a series of possible markers associated with it, and some markers may attach to more than one different sites. The number of markers for each site totals between 3 and 20 or so. Some are very rare and some are very common associations, but with 20 possible areas and several hundred in total markers there is sufficient information to exclude everyone else from identification to very high levels of probability.
Different jurisdictions make different assessments of how many markers are required for such identification to be legally valid.
Anything contentious so far?
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Where do we get our DNA from? We get roughly half from our mother and half from our father. So each child will share on average 50% of their mother's DNA and 50% of their father's DNA. This includes the pattern of positions and markers used to identify people using DNA.
Why did Madeleine have only 19 potential area/marker matches? Because Kate and Gerry shared on marker/position piece of information, meaning that only 19 different ones were available rather than 20.
Full siblings will share on average 25% of such position/marker pairs.
Any problems?
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What is LCNDNA analysis and how does it differ from ordinary DNA analysis?
Ordinary DNA analysis has a considerable amount of DNA available for analysis. The sample is acted on chemically to separate the DNA into smaller strands and then identification of strands is made looking for the sites required and determining which markers are attached to those sites. What results is a list of sites and markers allowing clear identification to be made.
LCNDNA analysis is a technique developed to determine what information is available in an inadequate sample for full DNA analysis. It works by causing the very small amount of DNA information to produce copies of itself until enough DNA is produced to start drawing conclusions from it. There is not as much information available as in normal DNA testing and site/marker pairing may be much more difficult. It is also open to major problems with cross contamination as the amounts being worked on are very close to those amounts transferred naturally to a sample by simple contact if the sample is not placed immediately in a safegiarded environment to maintain the chain of evidence. Even breathing on the sample, or a tiny particle of skin detritus could result in cross contamination.
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So what about the back of the scenic. We know that the car had been used by Gerry, Kate, Sean and Amelie for three weeks and that rubbish had been carried in the back of the car. It is almost inconceivable that some of their DNA had not been deposited in various parts of the car including the wheel well. A mixture of DNA from any or all of those four people would show up under LCNDNA analysis as potentially from Madeleine, even if she had never been in that car.
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What is LCNDNA analysis and how does it differ from ordinary DNA analysis?
Ordinary DNA analysis has a considerable amount of DNA available for analysis. The sample is acted on chemically to separate the DNA into smaller strands and then identification of strands is made looking for the sites required and determining which markers are attached to those sites. What results is a list of sites and markers allowing clear identification to be made.
LCNDNA analysis is a technique developed to determine what information is available in an inadequate sample for full DNA analysis. It works by causing the very small amount of DNA information to produce copies of itself until enough DNA is produced to start drawing conclusions from it. There is not as much information available as in normal DNA testing and site/marker pairing may be much more difficult. It is also open to major problems with cross contamination as the amounts being worked on are very close to those amounts transferred naturally to a sample by simple contact if the sample is not placed immediately in a safegiarded environment to maintain the chain of evidence. Even breathing on the sample, or a tiny particle of skin detritus could result in cross contamination.
Just to clarify Db. Could this cross contamination (e.g.from breathing on it etc) have already happened before the sample reached the lab - or are you just referring to what could happen during the test procedures?
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What was discovered by the FSS?
The sample was too small for regular DNA analysis so was submitted to LCNDNA analysis using replication of the strands. The result was a collection of (I think) 39 markers/locations meaning that at least two people were involved; the FSS with access to the full information estimated that at least three and maybe five people contributed to the sample.
In this set of markers, 15 were the same as possessed by Maddie (not surprising as there is a strong possibility that some of the DNA traces may have come from people using the car (including the McCannfamily who between them would have all of Madeleine's markers- 50% in each parent, 100% if both parents, 25% each sib and about 50% for both sibs.
Even ignoring family contribution, the fact that it cannot be said that all 15 of the markers indicating Madeleine came from a single person. Such marker/site signs are shared by many people across an historically interbreeding population.
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What is LCNDNA analysis and how does it differ from ordinary DNA analysis?
Ordinary DNA analysis has a considerable amount of DNA available for analysis. The sample is acted on chemically to separate the DNA into smaller strands and then identification of strands is made looking for the sites required and determining which markers are attached to those sites. What results is a list of sites and markers allowing clear identification to be made.
LCNDNA analysis is a technique developed to determine what information is available in an inadequate sample for full DNA analysis. It works by causing the very small amount of DNA information to produce copies of itself until enough DNA is produced to start drawing conclusions from it. There is not as much information available as in normal DNA testing and site/marker pairing may be much more difficult. It is also open to major problems with cross contamination as the amounts being worked on are very close to those amounts transferred naturally to a sample by simple contact if the sample is not placed immediately in a safegiarded environment to maintain the chain of evidence. Even breathing on the sample, or a tiny particle of skin detritus could result in cross contamination.
Just to clarify Db. Could this cross contamination (e.g.from breathing on it etc) have already happened before the sample reached the lab - or are you just referring to what could happen during the test procedures?
Anytime before the replication procedure started would be dangerous.
You are probably referring to the myth used by [ censored word ]s that Lowe said that people from his lab contributed their DNA to the sample. What he actually said was that the identification was at such a low level of confidence because the 39 (was it 37?) alleles would be found in the admixture of any 3-5 western European's DNA recovered in this manner and with no data about the provenance- and in passing said that it was possible that such a sample from people in his lab could produce these alleles.
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Why is ordinary DNA analysis so specific.
If you know that you have only 20 markers and they are all from the same person, each ID decreases the possibility of the sample being from someone else.
Suppose for arguments sake that only one person in a hundred had each marker (this is a gross simplification) and that the world population is 6 billion.
One marker reduces the potential population to 600 000 000
Two to 60 000 000
Three to 6 000 000
Four to 600 000
Five to 60 000
Six to 6000
Seven to 600
Eight to 60
Nine to 6
Ten and onwards to less than one, thus IDing a single individual to a certain level of assurance.
This power relationship does not hold for mixed samples- we are now doing what is called perming- the math is really quite difficult.
Say there were 40 markers found (for simplicity of calculation and five potential donors.
Marker one has a one chance in five of being from the target person and therefore the chance of this being from that person or from another person donating to the sample has to be calculated. This goes for each of the markers identified. So you do not get the progressive certainty that straight DNA analysis gives you as you have to allow for the marker being examined being from a different donor. In fact the certainty is so much reduced that any admixture of five different donor's partial DNA markers is that about fifty percent of them would include the fifteen markers identified.
And this excludes the possibility that one or more of the donors may have been relations with shared markers in abundance.
But don't think that this is going to convince the ............
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Some cites:
http://www.cps.gov.uk/publications/prosecution/lcn_testing.html
http://en.wikipedia.org/wiki/Low_copy_number
http://www.promega.co.uk/resources/articles/profiles-in-dna/lcn-dna-analysis-limitations-prevent-general-acceptance/?__utma=1.492364517.1366882780.1366882780.1366882780.1&__utmb=1.1.10.1366882780&__utmc=1&__utmx=-&__utmz=1.1366882780.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)&__utmv=-&__utmk=63540015
http://www.theforensicinstitute.com/news/low-copy-number-dna-and-the-forensic-institute.html
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If we take a sample of tissue or blood or other substancefrom a person or a crime scene, and this is found to have complete unbroken strands of DNA in it, then ordinary DNA analysis can be done.
This is carried out by a process that strips the DNA strands and allows scientists to identify particular short lengths of DNA with a recognisable pattern of complex chemical elements attached in certain places.
It has been shown that these chosen areas (a different number and different locations in different jurisdictions) contain sufficient variety of structure to make rational decisions about whether different samples do in fact match to a level of probability suitable to make a scientifically and forensically valid conclusion.
This complexity is because these twenty sites (In current usage) have a variety of chemical structures (called here 'markers' (elsewhere alleles) which are associated with these particular locations. Each area has a series of possible markers associated with it, and some markers may attach to more than one different sites. The number of markers for each site totals between 3 and 20 or so. Some are very rare and some are very common associations, but with 20 possible areas and several hundred in total markers there is sufficient information to exclude everyone else from identification to very high levels of probability.
Different jurisdictions make different assessments of how many markers are required for such identification to be legally valid.
Anything contentious so far?
I have a slight problem DB. The distinction between "markers" and "alleles" has been a source of confusion throughout this case. My understanding is that the forensic labs look for two alleles at each locus used in their forensic analysis system. The locus (site) is often referred to as a marker.
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If we take a sample of tissue or blood or other substancefrom a person or a crime scene, and this is found to have complete unbroken strands of DNA in it, then ordinary DNA analysis can be done.
This is carried out by a process that strips the DNA strands and allows scientists to identify particular short lengths of DNA with a recognisable pattern of complex chemical elements attached in certain places.
It has been shown that these chosen areas (a different number and different locations in different jurisdictions) contain sufficient variety of structure to make rational decisions about whether different samples do in fact match to a level of probability suitable to make a scientifically and forensically valid conclusion.
This complexity is because these twenty sites (In current usage) have a variety of chemical structures (called here 'markers' (elsewhere alleles) which are associated with these particular locations. Each area has a series of possible markers associated with it, and some markers may attach to more than one different sites. The number of markers for each site totals between 3 and 20 or so. Some are very rare and some are very common associations, but with 20 possible areas and several hundred in total markers there is sufficient information to exclude everyone else from identification to very high levels of probability.
Different jurisdictions make different assessments of how many markers are required for such identification to be legally valid.
Anything contentious so far?
I have a slight problem DB. The distinction between "markers" and "alleles" has been a source of confusion throughout this case. My understanding is that the forensic labs look for two alleles at each locus used in their forensic analysis system. The locus (site) is often referred to as a marker.
That was why I was trying to avoid complex words. Site and marker are simplifications but do not affect the calculations or truth of what is being said. Additionally Allele and Locus are complex latinate worlds with non-generalist acceptance whereas site and marker are simple words.
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If we take a sample of tissue or blood or other substancefrom a person or a crime scene, and this is found to have complete unbroken strands of DNA in it, then ordinary DNA analysis can be done.
This is carried out by a process that strips the DNA strands and allows scientists to identify particular short lengths of DNA with a recognisable pattern of complex chemical elements attached in certain places.
It has been shown that these chosen areas (a different number and different locations in different jurisdictions) contain sufficient variety of structure to make rational decisions about whether different samples do in fact match to a level of probability suitable to make a scientifically and forensically valid conclusion.
This complexity is because these twenty sites (In current usage) have a variety of chemical structures (called here 'markers' (elsewhere alleles) which are associated with these particular locations. Each area has a series of possible markers associated with it, and some markers may attach to more than one different sites. The number of markers for each site totals between 3 and 20 or so. Some are very rare and some are very common associations, but with 20 possible areas and several hundred in total markers there is sufficient information to exclude everyone else from identification to very high levels of probability.
Different jurisdictions make different assessments of how many markers are required for such identification to be legally valid.
Anything contentious so far?
I have a slight problem DB. The distinction between "markers" and "alleles" has been a source of confusion throughout this case. My understanding is that the forensic labs look for two alleles at each locus used in their forensic analysis system. The locus (site) is often referred to as a marker.
That was why I was trying to avoid complex words. Site and marker are simplifications but do not affect the calculations or truth of what is being said. Additionally Allele and Locus are complex latinate worlds with non-generalist acceptance whereas site and marker are simple words.
I'm not sure that I've adequately explained my concern....
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I see what you mean. If people can just think site and molecule then.
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Where do we get our DNA from? We get roughly half from our mother and half from our father. So each child will share on average 50% of their mother's DNA and 50% of their father's DNA. This includes the pattern of positions and markers used to identify people using DNA.
Why did Madeleine have only 19 potential area/marker matches? Because Kate and Gerry shared on marker/position piece of information, meaning that only 19 different ones were available rather than 20.
Full siblings will share on average 25% of such position/marker pairs.
Any problems?
Perhaps this could be a better starting point?
NB: Forensic scientists are not examining the entire DNA of a person.
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I see what you mean. If people can just think site and molecule then.
I'm interested in your explanation.
However, I think you're going too fast for common mortals (including myself) to follow. And those who are aware of how LCNDNA works probably already understand what the issue is.
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The essence is that there is far more information in a clean example that is not contaminated.
LCNDNA analysis is firstly open to contamination, and if it is incomplete and mixed ( as the Scenic sample was) holds less information.
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
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Any takers?
Seems to be a deafening silence when confronted with facts.
What facts ?
... havn't seen any proposed on this thread so far
What, exactly, are we meant to be 'confronting' here
You asked this question.I see you are on line now. I note you are still not confronting the facts.
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I think this from Lowe's email to Stuart Prior provides the answer, doesn't it?
What questions will we never be able to answer with LCN DNA profiling -
When was the DNA deposited -
How was the DNA deposited -
What body fluid(s) does the DIVA originate from -
Was a crime committed -
Of course, in context, he is referring, specifically, to LCN DNA as it applies to results from the boot of the car.
He is not making a general comment about LCN DNA which, for example, finally solved the crime of the murder of Stephen Lawrence and put the culprits in prison.
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I think this from Lowe's email to Stuart Prior provides the answer, doesn't it?
What questions will we never be able to answer with LCN DNA profiling -
When was the DNA deposited -
How was the DNA deposited -
What body fluid(s) does the DIVA originate from -
Was a crime committed -
Of course, in context, he is referring, specifically, to LCN DNA as it applies to results from the boot of the car.
He is not making a general comment about LCN DNA which, for example, finally solved the crime of the murder of Stephen Lawrence and put the culprits in prison.
That was BEFORE he knew that he sample was a mix of 3-5 different people's partial DNA.
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I think this from Lowe's email to Stuart Prior provides the answer, doesn't it?
What questions will we never be able to answer with LCN DNA profiling -
When was the DNA deposited -
How was the DNA deposited -
What body fluid(s) does the DIVA originate from -
Was a crime committed -
Of course, in context, he is referring, specifically, to LCN DNA as it applies to results from the boot of the car.
He is not making a general comment about LCN DNA which, for example, finally solved the crime of the murder of Stephen Lawrence and put the culprits in prison.
That was BEFORE he knew that he sample was a mix of 3-5 different people's partial DNA.
No it wasn't.
From the same email:
A complex LCN DNA result which appeared to have originated from at least three people was obtained from cellular material recovered from the luggage compartment section 286C 2007 CRL10 (2) area 2. Within the DNA profile of Madeline McCann there are 20 DNA components represented by 19 peaks on a chart. At one of the areas of DNA we routinely examine Madeleine has inherited the same DNA component from both parents; this appears therefore as 1 peak rather than 2, hence 19 rather than 20. Of these 19 components 15 are present within the result from this item; there are 37 components in total. There are 37 components because there are at least 3 contributors; but there could be up to five contributors. In my opinion therefore this result is too complex for meaningful interpretation/inclusion.
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I think this from Lowe's email to Stuart Prior provides the answer, doesn't it?
What questions will we never be able to answer with LCN DNA profiling -
When was the DNA deposited -
How was the DNA deposited -
What body fluid(s) does the DIVA originate from -
Was a crime committed -
Of course, in context, he is referring, specifically, to LCN DNA as it applies to results from the boot of the car.
He is not making a general comment about LCN DNA which, for example, finally solved the crime of the murder of Stephen Lawrence and put the culprits in prison.
That was BEFORE he knew that he sample was a mix of 3-5 different people's partial DNA.
No it wasn't.
From the same email:
A complex LCN DNA result which appeared to have originated from at least three people was obtained from cellular material recovered from the luggage compartment section 286C 2007 CRL10 (2) area 2. Within the DNA profile of Madeline McCann there are 20 DNA components represented by 19 peaks on a chart. At one of the areas of DNA we routinely examine Madeleine has inherited the same DNA component from both parents; this appears therefore as 1 peak rather than 2, hence 19 rather than 20. Of these 19 components 15 are present within the result from this item; there are 37 components in total. There are 37 components because there are at least 3 contributors; but there could be up to five contributors. In my opinion therefore this result is too complex for meaningful interpretation/inclusion.
Sorry. I thought it was from the initial report.
It makes no difference to my contention about the statistics.
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
Amaral & co., might, I suppose. Lowe tried to explain, as did Corte-Real (who agreed with Lowe).
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
Amaral & co., might, I suppose. Lowe tried to explain, as did Corte-Real (who agreed with Lowe).
Possibly.
I was referring to rebuttal from people on this site who have insisted erroneously that Madeleine's DNA was found in the Scenic.
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
No, there is no evidence that it was.
But Mr Lowe of the FSS said it was not possible to say one way or the other, so the possibility remains. It was an inconclusive result, not a ruled out possibility.
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
No, there is no evidence that it was.
But Mr Lowe of the FSS said it was not possible to say one way or the other, so the possibility remains. It was an inconclusive result, not a ruled out possibility.
you would of course be prepared to present a case in court based on what you said? (if it was your job)
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
No, there is no evidence that it was.
But Mr Lowe of the FSS said it was not possible to say one way or the other, so the possibility remains. It was an inconclusive result, not a ruled out possibility.
Which means that it is as likely to have been Madeleine's alleles as any member of, say, the PJ. No evidentiary value in separating her DNA from that of the rest of the population of Europe.
Glad that you understand that.
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So I assume from the lack of any attempt at rebuttal that we all agree that there is no evidence that Madeleine's DNA was found in the Scenic.
Maybe people will cease claiming that that is true.
No, there is no evidence that it was.
But Mr Lowe of the FSS said it was not possible to say one way or the other, so the possibility remains. It was an inconclusive result, not a ruled out possibility.
Which means that it is as likely to have been Madeleine's alleles as any member of, say, the PJ. No evidentiary value in separating her DNA from that of the rest of the population of Europe.
Glad that you understand that.
Maybe, but the FSS said it is impossible to say one way or the other, so whilst there is no EVIDENCE, there also is no evidence it wasnt, those are the facts
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Any takers?
No, we shall NOT.