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Archiver > GENEALOGY-DNA > 2008-05 > 1211149330


From: Nelda Percival <>
Subject: Re: [DNA] Y-DNA tEsting
Date: Sun, 18 May 2008 17:22:10 -0500
References: <c34.31fbc4eb.3561f68a@aol.com>
In-Reply-To: <c34.31fbc4eb.3561f68a@aol.com>


Hi,
your:I take it, it doesn't matter at what point the differences occur, but the number of steps difference (I know they have to be on the same marker).

answer: yes, it does not matter on what marker the difference appears. the total accumulation of steps/differences matters.

your: That's why someone could match on 12 and be looking good, but then on 25 a few could start dropping out of the kinship group depending on the number of steps of differences per person.

answer normally yes.. but as has been pointed out if you had two men who were say 7 markers apart but both had a wierd result on one marker (each matching the other here) then you have to look closer at the relationship. because they are related due to the oddity of the result. the percentage of it happing randomly to two people of the same surname would be astronomical. that is where you bring it here to those genetists that monitor the mailing list...

We have 7 members of our Group. One participant did the 67, and two did 37 > only and one did 25. All are exact matches at 12, there are two that are exact > matches at 37 (one being my male direct line cousin matching the 67 marker > participant). The only 25 marker test has a two step difference from my > cousin and his 37 marker match. The other 37 marker member had a one step > difference from the other two 37s and if I'm understanding correctly, a three step > difference from the 25 marker guy.

Ok here I have not read that book.> > So then I read "Interpreting Genetic Distance Within Surname Projects", but > it was re 12 markers. Does the same rule apply if it's 67 markers?

ANSWER: But, the powers that be have taken slow changing markers and fast changing markers and developed a rule of thumb for the distance to the common ancestor. Yes it matters if your change is at a fast or slow marker but I'm not good enough to tell you why or how. basically I use 30 years for one generation so if I was indicated as having a common ancestor at 15 denerations it is 15 x 30 = so about 450 years as the medium looking sooner up to 300 years and backwards to 800 years. Remember, there is no factual rule here it is done on guesimations of the distance of years between the birth of the father and birth of the son.

your: Does it matter which marker it occurred on?
answer yes, but that is where I let the experts here decide.. remember fast mutating slow mutating.

your: Also, if you are one step distance at 12, and then upgrade to 67 (or would you bother at that point), does the one step lessen in significance. Or is one step, one step....
Answer: one step is one step neither giant or small.

If i had two men 6 steps apart at 25 / 37 markers then they both tested at 67 markers and still only had 6 steps in difference I would tell them to look for their common ancestor, but I wouldn't at 25 / 37 markers just because it might break down by the time it hit 67 markers. this is one of the reasons to do as many markers as you can the match is more confirmed.

your: is there any reason for my cousin to upgrade to 67? Will it tell more about the > relationship with the exact 37 marker match guy.
answer: genetics tell you your related or not nothing else really.

Personally, I would only ask members to test to 67 markers if I had a very large group of almost matching individuals that I was trying to break down into family groupings.


I like SNP testing, and think it more important to positivly identify your haplogroup then breaking the groups into families. (so if I can I like to get them to at least have a backbone test of their particular haplogroup.

your: To my knowledge none of these guys have a paper trail back to the ancestor everyone is hoping for. We sure don't. We are corresponding with one of them and he's very confident of the ancestry, but with nothing to back it up. I can't even find where we relate without going back 10 generations to our "supposed" ancestry.
ANSWER: My line stops in 1828 Ohio On the chart you looked at I'm G1, you saw the relationship betwen G1 / G2 / G6 we are presently looking for where we relate at. It is thought that G2 is the oldest and that possibly G6 and G1 descend from him or his father, but we have no paper work connecting us...

We hunt! and your guys will have to do the work of documenting the connection too.


Nelda

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