11 for 12 marker matching

[crowslanding]

Greetings. I'm the Crow(e) Group DNA Administrator and wonder why FTDNA doesn't report 11 for 12 matches to it's customers, since I've read somplace on this site, that even brothers could test and match 11 for 12. I believe the wording was something like "mutations happen on a regular basis, but can happen at any time".

In my case, I've many DNA new cousins, but some only matching 11 for 12.

I know on the 25 marker test, FTDNA is currently allowing 23 & 24 for 25 as matches, or did I miss something?

[admin]

Re: 11 for 12 marker matching

Originally posted by crowslanding
Greetings. I'm the Crow(e) Group DNA Administrator and wonder why FTDNA doesn't report 11 for 12 matches to it's customers, since I've read somplace on this site, that even brothers could test and match 11 for 12. I believe the wording was something like "mutations happen on a regular basis, but can happen at any time".

In my case, I've many DNA new cousins, but some only matching 11 for 12.

I know on the 25 marker test, FTDNA is currently allowing 23 & 24 for 25 as matches, or did I miss something?

We have always said that DNA is a research tool to be used in conjuction with traditional genealogy research. Our approach is that the 12 marker test - which has become a standard test for genealogists to start with - is used to a) a tool for excluding relationships or b) a path for confirming relationships. In both cases it is up to the administrator, based on his/her objectives for the project and the paper trail, to decide whether to move on to the 25-marker test or not.
If you have documented proof of a relationship and the 12-marker is a confirmation tool, and, in your group tables you find a 11/12 match with a single mutation, you don't need to go for a general matching with the database. This will only pollute your results, since you may receive many matches from unrelated individuals (especially if we are talking about a R1b Haplogroup).
Don't look for relatives out of random matches in a situation of 11/12. Try to tie your results to the paper trail. It will end up confusing more than helping. We agreed to expand the matching on the 25 marker test because from the statistical standpoint it made more sense than expanding it to 11/12.
Other GA's are welcome to jump in and make their point.

[crowslanding]

Re: Re: 11 for 12 marker matching

Originally posted by max
We have always said that DNA is a research tool to be used in conjuction with traditional genealogy research. Our approach is that the 12 marker test - which has become a standard test for genealogists to start with - is used to a) a tool for excluding relationships or b) a path for confirming relationships. In both cases it is up to the administrator, based on his/her objectives for the project and the paper trail, to decide whether to move on to the 25-marker test or not.
If you have documented proof of a relationship and the 12-marker is a confirmation tool, and, in your group tables you find a 11/12 match with a single mutation, you don't need to go for a general matching with the database. This will only pollute your results, since you may receive many matches from unrelated individuals (especially if we are talking about a R1b Haplogroup).
Don't look for relatives out of random matches in a situation of 11/12. Try to tie your results to the paper trail. It will end up confusing more than helping. We agreed to expand the matching on the 25 marker test because from the statistical standpoint it made more sense than expanding it to 11/12.
Other GA's are welcome to jump in and make their point.

Thanks Max. That clears it up, and now I understand better why you do not report 11 for 12 matches, as matches. Phillip

[Mokurai]

Hi,

I accept the reasoning for not accepting the 11/12 match, as I do for accepting the 24/25 match, but am wondering if the 23/25 match isn't, perhaps, an equal billing to the 11/12 match? For example the 11/12 would be .916 percentage and the 23/25 would be .92 percentage...not much difference eh. And then a bit of a step up to 24/25 of .96 percent.

Hooray.