MADELEINE'S DNA - definitive study.

[Mr Gray]

No they haven't or if you think they have tell us please?

This is the answer from the file: "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."

That is not simple.
Who are three people in the mix that could give that result?

Three previous occupants of the car
It appears to me that the PJ asked the question
Can this sample confirm the presence of Maddies DNA in the car
The answer is a simple no

[Carana]

Imagine if the DNA result could simply be explained by a three person mixture of the Mother, the Mother's mother and a female sibling to Madeleine.  Excluding Madeleine?  That could be explained by a shopping trip with one of the twins in the Renault.

Why all female?

[jassi]

Did the result exclude the possible presence of Madeleine?

[Mr Gray]

Did the result exclude the possible presence of Madeleine?

Madeleine may have been in the car or she may not
The DNA doesn't tell us anything
But there is no evidence she was

[Carana]

(Snip)
Do you think a sample would ever have 9 or more alleles at a locus?

It's possible:

https://en.wikipedia.org/wiki/Second_Generation_Multiplex_Plus

[Robittybob1]

It's possible:

https://en.wikipedia.org/wiki/Second_Generation_Multiplex_Plus

OK that was very technical.  What sentence or table make you convinced it was possible?

[Robittybob1]

Why all female?

If there was a male plus Madeleine the sex allele would be x and y  so in a mix that could be both male and female in the mix.
If there were only females (like a spillage occurred on a shopping trip) the sex allele could just stay x.  We are looking for ways to keep the total down to 37 which I think is hard in a 3 person mix unless there is close relationship and genetically close to Madeleine too to include the 15 out of her 19 alleles.
In some cases a 3 person mix could end up with 60 alleles in total, 20 from each person.

[Robittybob1]

Did the result exclude the possible presence of Madeleine?

That is the question I have sent to Dan Krane.  I have not heard back yet.  But using his criteria: if alleles of the reference sample are missing from the evidence sample that reference person is excluded.  On that basis that 4 of Madeleine's alleles are missing in the evidence sample I would predict Dan will say she is excluded or as you put it "exclude the possible presence of Madeleine".
But I have been wrong before.

[Robittybob1]

Madeleine may have been in the car or she may not
The DNA doesn't tell us anything
But there is no evidence she was

That DNA result tells us a lot.  Remember we only have been told some little bits about the result and one of the reference samples they are working with.

[Mr Gray]

That DNA result tells us a lot.  Remember we only have been told some little bits about the result and one of the reference samples they are working with.

what does it tell us.....nothing of any use

[Robittybob1]

Why all female?

If we had a child plus her mother  plus her grandmother in the mix what is the maximum number of alleles that could be in the mix?

Daughter max = 20
Daughter  mother mix max number = 30
Daughter plus her mother  plus her grandmother = 45?? (max of 15 new ones)  So with a bit of homozygosity and commonality it could easily drop down to 37 in an actual 3 person mix involving "Daughter plus her mother  plus her grandmother".

[Robittybob1]

what does it tell us.....nothing of any use

That is because they what to keep these files secret.

[Mr Gray]

That is because they what to keep these files secret.

If they had found a perfect match to Maddie
What would that have told us
It wouldn't even confirm she had been in the car

[Robittybob1]

If they had found a perfect match to Maddie
What would that have told us
It wouldn't even confirm she had been in the car

From the position the samples were collected it would be very hard to explain a perfect unmixed evidence sample that matched Madeleine. (i.e. just the 19 alleles)  We would be thinking in terms of identical twins then.

[jassi]

Indeed it would, but I think you are in danger of drifting towards fantasy.

On the other hand, there was a good Maddie and then there was a bad Maddie according to Kate's mother (I think)