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Archiver > AUTOSOMAL-DNA > 2012-07 > 1342995088


From: Jim Bartlett <>
Subject: Re: [AUTOSOMAL-DNA] family finder results
Date: Sun, 22 Jul 2012 18:11:28 -0400
References: <BLU151-ds57025F0AAB002052866F3B5DE0@phx.gbl>
In-Reply-To: <BLU151-ds57025F0AAB002052866F3B5DE0@phx.gbl>


CeCe, et al,

If you've made a spreadsheet of all your matching segments, you are on the right track. As CeCe does, sort by Chr and SegmentStartLocation - this then is your map. It's a combination of segments from Dad's side and Mom's side, all mixed together. If you could phase every segment you'd know which parent each segment came from and you could divide the spreadsheet into two parts.

For those who don't/can't do phasing: I've added a column to my spreadsheet for a Segment Code. I look down each Chr and try to estimate how to code groups of segments - and then assign letters, a-z, for each group - it's a judgement call. So the first segment group on Chr06 would get 06a; the last one might be 06t. As I found Common Ancestors for certain segments, I'd know if it was on Dad's side or Mom's, and I would add a 2 (for Dad) or 3 (for Mom). 2 and 3 are the standard ahnentafel numbers for your parents.

If you also had a separate column for the 2 or 3, you could at any time sort your spreadsheet by that column. It wouldn't mean much until you had determined 50-100 Common Ancestors. Then you could sort them by the 2/3 column, and by Chr and by Start. You should see all the segment codes (for each group of overlapping segments) in each phase in order, with no overlap.

Note: when known close cousins are tested, you know quickly if a 2 or 3 goes with the segment they share with you.

Sometimes, when you know your matches on the same/overlapping segment match each other, then you can assume they will both share the same Common Ancestor with you, and be in the same phase. If you can determine two of your matches are not related, then they would come from different phases. These clues add up.

Jim - Sent from my iPhone - FaceTime!

On Jul 22, 2012, at 4:22 PM, "CeCe Moore " <> wrote:

> Patricia,
> The way I do it (for now) is decidedly low tech. I keep a spreadsheet that is combined from all of the downloads of my known relatives on FI:A, sorted on Chromosome, then start point. I add a column for P or M depending which side the cousin is on. (You can separate the Paternal and Maternal spreadsheets if you want.) Then I compare unknown matches to them.
> To copy the image I posted, if you can, do screen grabs of Family Inheritance Advanced and then overlay them in Photoshop and change the color to code for each great grandparent or gggrandparent or just simply print them and use them as a guide to draw them in by hand (use the three relatives from different ancestral lines with the most DNA in common as your printed starting chart - then follow that color coding). This is far from exact, of course, but is good for quick reference to check and see if I have a ancestor mapped yet in the general area of a new match. If I do, I know to open the spreadsheet and check the exact spot.
> With 13 known relatives, you should have a pretty cool map started.
> I will eventually do something like what Tim is doing. I just haven't had the time to do it yet and I am non-techie like you! Good luck!!
> CeCe
> Sent via BlackBerry by AT&T
>


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