Amaral and the dogs

[stephen25000]

if you understood it you would see what she has achieved

Unfortunately dave, I do know know what Venn diagrams are and when to apply them.

Next.

[Mr Gray]

Unfortunately dave, I do know know what Venn diagrams are and when to apply them.

Next.

then you should understand what a stirling job Carana has done

[Mr Gray]

In missing children s cases, parents are investigated.

It's a matter of course.

of course they are and quite rightly too

[stephen25000]

then you should understand what a stirling job Carana has done

So if I had copied and pasted that, would I have done a sterling job  ?

[Mr Gray]

So if I had copied and pasted that, would I have done a sterling job  ?

no

[stephen25000]

no

 

[Carana]

You two. 

I found a way of understanding the issue as a non-scientist. Some people may find it helpful, others won't.

If my understanding of the issue is manifestly wrong, then do help by providing a correct explanation in words of one syllable or less in a way that anyone can comprehend.

Here is what Lowe said in his 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.

Why - ...

Well lets look at the question that is being asked

"Is there DNA from Madeline on the swab "

It would be very simple to say "yes" simply because of the number of components within the result that are also in her reference sample.

What we need to consider, as scientists, is whether the match is genuine and legitimate; because Madeline has deposited DNA as a result of being in the car or whether Madeline merely appears to match the result by chance. The individual components in Madeline's profile are not unique to her, it is the specific combination of 19 components that makes her profile unique above all others. Elements of Madeline's profile are also present within the the profiles of many of the scientists here in Birmingham, myself included. it's important to stress that 50% of Madeline's profile will be shared with each parent. It is not possible in a mixture of more than two people, to determine or evaluate which specific DNA components pair with each other. Namely, we cannot separate the components out into 3 individual DNA profiles.

Therefore, we cannot answer the question: is the match genuine or is it a chance match.

The same applies to any result that is quoted as being too complex for meaningful inclusion/interpretation

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 -

These, along with all other results, will be formalised in a final report

Please don't hesitate to contact me if you require any further assistance



And here is my Venn diagram again:

[stephen25000]

You two. 

I found a way of understanding the issue as a non-scientist. Some people may find it helpful, others won't.

If my understanding of the issue is manifestly wrong, then do help by providing a correct explanation in words of one syllable or less in a way that anyone can comprehend.

Here is what Lowe said in his 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.

Why - ...

Well lets look at the question that is being asked

"Is there DNA from Madeline on the swab "

It would be very simple to say "yes" simply because of the number of components within the result that are also in her reference sample.

What we need to consider, as scientists, is whether the match is genuine and legitimate; because Madeline has deposited DNA as a result of being in the car or whether Madeline merely appears to match the result by chance. The individual components in Madeline's profile are not unique to her, it is the specific combination of 19 components that makes her profile unique above all others. Elements of Madeline's profile are also present within the the profiles of many of the scientists here in Birmingham, myself included. it's important to stress that 50% of Madeline's profile will be shared with each parent. It is not possible in a mixture of more than two people, to determine or evaluate which specific DNA components pair with each other. Namely, we cannot separate the components out into 3 individual DNA profiles.

Therefore, we cannot answer the question: is the match genuine or is it a chance match.

The same applies to any result that is quoted as being too complex for meaningful inclusion/interpretation

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 -

These, along with all other results, will be formalised in a final report

Please don't hesitate to contact me if you require any further assistance



And here is my Venn diagram again:

 

[ShiningInLuz]

...

In the UK, they examine 10 marker (locations), i.e. 20 alleles. In PT, they examine 15, i.e., 30 alleles. 

...

Do you have a cite for the second part of that?

Does this mean that sending samples for DNA testing to the FSS was a waste of time, as the 'evidence' would not be allowed in a Portuguese court, given that it does not meet Portuguese requirements?

[Mr Gray]

Do you have a cite for the second part of that?

Does this mean that sending samples for DNA testing to the FSS was a waste of time, as the 'evidence' would not be allowed in a Portuguese court, given that it does not meet Portuguese requirements?

A DNA profile is simply a count of these short tandem repeats at particular locations on the genome. The CODIS database developed by the FBI uses STR at 13 places, and the UK National DNA database uses STR at 10 places.

from the little I have read no one these forums really understands the DNA evidence. It is further complicated by the fact that some allelles are far more common than others. if maddie had some of these rare allelles then the sample would be more significant...if the allelles were common ..much less significant.

[Carana]

Do you have a cite for the second part of that?

Does this mean that sending samples for DNA testing to the FSS was a waste of time, as the 'evidence' would not be allowed in a Portuguese court, given that it does not meet Portuguese requirements?

I have no idea where it has been stated that results would be inadmissible in a Portuguese court per se, other than in blogs and TV pundit "experts". I see no reason why they couldn't be, but simply not submitted as conclusive evidence.


PT doesn't have (or didn't) the sterile facilities needed for LCN in any case.


The UK uses 10 (SGM+), the FBI uses 13 and PT (and several other countries) use 15 - again within the context of standard criminal forensic tests. There is also another marker to add to those which simply determines sex.

On the samples that the INML tested, they used two different kits (not all marker locations are universally used). The INML lab bent over backwards and checked for more... but obviously only on what they were actually given to test with regard to nuclear DNA.




4-Nuclear DNA study

After extraction the following genetic markers were studied by PCR:

- Autosomic STRs: D8S1179, D21S11, D7S820, CSFlPO, D3S1358, HUMTH01, D13S317, D16S539, D2S1338, D19S433, HUMVWA31/A, TPOX, D18S51, D5S818, HUMFIBRA/FGA and Amelogene, using the primers and conditions of amplification suggested in the kit AmpFISTR Identifiler (Applied Bioystems).

- Autosomic STRs: D3S1358, HUMTH01, D21S11, D18S51, Penta E, D5S818, D13S317, D7S820, D16S539, CSFlPO, Penta D, HUMVWA31/A, D8S1179, TPOX, HUMFIBRA/FGA, and Amelogene using the primers and the conditions of amplification suggested in kit PowerPlex(tm)16 System (Promega).
http://www.mccannpjfiles.co.uk/PJ/PORTUGUESE-FORENSIC.htm

[Carana]

A DNA profile is simply a count of these short tandem repeats at particular locations on the genome. The CODIS database developed by the FBI uses STR at 13 places, and the UK National DNA database uses STR at 10 places.

from the little I have read no one these forums really understands the DNA evidence. It is further complicated by the fact that some allelles are far more common than others. if maddie had some of these rare allelles then the sample would be more significant...if the allelles were common ..much less significant.

And PT used both Applied Biosytems and Promega kits (with a common core, but also extra ones to potentially detect). But the INML could only work with the samples that they were given and didn't have the capacity to do LCN tests, if needed.

[Carana]

A DNA profile is simply a count of these short tandem repeats at particular locations on the genome. The CODIS database developed by the FBI uses STR at 13 places, and the UK National DNA database uses STR at 10 places.

from the little I have read no one these forums really understands the DNA evidence. It is further complicated by the fact that some allelles are far more common than others. if maddie had some of these rare allelles then the sample would be more significant...if the allelles were common ..much less significant.

Yes, because they were only looking at standard loci for criminal forensic purposes.

[Carana]

Picking up on a point re legal issues, there is a difference between either party stating that a significant proportion of Madeleine's DNA was present (again with the caveat that such tests are limited) and establishing your identity in a paternity / maternity suit.

In the former, there is a possibility that you were in a certain location when the swabs were taken.

But you can't go to court and state that you are definitely the child of X based on a degraded and contaminated sample taken 3 months later from a car boot used by a multitude of people including close family.

[ferryman]

Picking up on a point re legal issues, there is a difference between either party stating that a significant proportion of Madeleine's DNA was present (again with the caveat that such tests are limited) and establishing your identity in a paternity / maternity suit.

In the former, there is a possibility that you were in a certain location when the swabs were taken.

But you can't go to court and state that you are definitely the child of X based on a degraded and contaminated sample taken 3 months later from a car boot used by a multitude of people including close family.

The last three words being key.

Would certainly explain a high number of alike markers (without contribution from the person of key interest, Madeleine ...)