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General => Ancestral Family Tree DNA Testing => Topic started by: Ruskie on Thursday 01 February 18 06:12 GMT (UK)
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I am looking at two of my matches and our shared segments on the FTDNA Family Finder Chromosome Browser and would be grateful for some help.
They are both predicted to be 2nd to 4th cousins. I know that "N" is a second cousin once removed, but I have no idea how "P" and I connect.
These two matches do not match each other anywhere so my relationship with N and P must be on different branches of my family.
The matches with "P" are quite significant I assume? They are as follows:
PB matches you on chromosome 10 from position 24868750 to 49437552 for a total of 18.64 cM.
PB matches you on chromosome 10 from position 55717476 to 89348652 for a total of 35.79cM.
PB matches you on chromosome 10 from position 119223365 to 127738898 for a total of 16.63 cM.
PB matches you on chromosome X from position 38886494 to 41030869 for a total of 5.71 cM.
PB matches you on chromosome X from position 147012373 to 149379258 for a total of 5.26 cM.
Can someone please explain the significance of the matches on Chromosome 10? And the X matches?
Just for comparison, these are the matches I have with "N" my proven second cousin once removed:
N matches you on chromosome 1 from position 5601705 to 9016716 for a total of 5.67 cM.
N matches you on chromosome 4 from position 54662466 to 61361342 for a total of 7.77 cM.
N matches you on chromosome 9 from position 86674433 to 94909764 for a total of 13.5 cM.
N matches you on chromosome 18 from position 72872188 to 76116152 for a total of 11.97 cM.
N matches you on chromosome 19 from position 44647355 to 63788972 for a total of 45.71 cM.
Can anything be gleaned from these chromosome positions? I am guessing if I can't find a paper trail, there is nothing in these numbers that will help me?
Thanks in anticipation. :)
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I don't know if this will be of any help, but I was asking something similar the other day
http://www.rootschat.com/forum/index.php?topic=786693.0
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Thanks colmc. Confusing isn't it? :-\
It sounds like you are trying to match up yourself and others to work out where you all connect, whereas I am just trying to find a match with myself and one other person who seems to match a large amount on Chromosome 10.
I am hoping someone can tell me what all the numbers indicate, if anything ...
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Ruskie, not much can be read into the position you match on.
Have you run PB and N through the In Common With function?
Re X matches - anything under 20 is considered most likely a false match.
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Thanks Spike.
I just had a look at the "in common" function. PG only matches one other person, a 5th to remote cousin, so I don't know how useful that is?
"N" has 19 matches. :-\
What do these matches tell me?
I will dismiss the X matches as red herrings.
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19 is good!
Now you put them in the Chromosome browser - five at a time it allows - and see which ones match N on the same segments that you match with N.
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I just did that with PB and the one other match and there seem to be no matches at all.
I will look at N's matches now. :)
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I have only compared 5 so far. :)
Two of N's matches match on chromosone 6 - one 8.79 cM and the other 9.29 cM.
I am a bit confused. Do these two matches only match with N? Do I need to match on the same positions to find a link?
I will compare the others ...
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Similar with another two matching on similar positions on chromosome 2 - one 11.05 cM and the other 9.21 cM.
And again on 19, one 10.05 cM and the other 9.55 cM.
No more matches/overlaps with the other people N matches with. :-\
I think I will keep playing with the "in common with" function to see if I can discover more.
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As there is only one other match with P, but P and I seem to have such a good match on chromosome 10, but only chromosome 10 now that the X matches are out of the equation, what does that mean?
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Means that none of your rellies have tested yet ;)
And yes re ICW, you and N and the other all have to match on an overlap of the segments you mentioned.
I hope you have uploaded to GEDmatch. You get to check against Ancestry users and others. Tools are good too.
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Means that none of your rellies have tested yet ;)
Yes, I understand that. But my matches with N are spread over various chromosomes, whereas my match with PB is only on 10, and it is a fairly large match.
I can see some overlapping segments with myself, N and three other people. Due to the surnames of those tested and my knowledge of where N and I match paper trail wise, I am pretty sure these connect through my Irish ancestors.
Yes, I uploaded to Gedmatch some time ago. I did play around with it but got completely lost. I shall try again.
Thanks for your help. It is all becoming a little clearer. :)
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19 is good!
Now you put them in the Chromosome browser - five at a time it allows - and see which ones match N on the same segments that you match with N.
Thank you spike I do think you have mostly answered this but if I could confirm. One of my brickwalls is bugging me so I put the name in and had 15 matches with that name ( FamilyFinder) I clicked on 5 that matched with other names and they all have colour on different segments . ie none are on the same chromosone line let alone overlap.
Does this mean they dont match each other and only match me on those segments ?
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That would be correct, David.
But we were talking about the In Common With function and you seem to be looking at those people who have matches in common with only you.
You might want to select some of those matches and see who else they match using ICW. This will bring in genuine matches who are not showing the surname you have used for your filter. Alternatively you could download all your matching segments to a spreadsheet, and finding those 15 matches will show who else they match with.
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Thank you spike
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A secondary question : ftDNA show chromosomes as a segmented piece ie 2 segments
(http://forums.familytreedna.com/showthread.php?t=38112)
Is there a specific side to maternal and paternal sides? ie does the left hand segment hold paternal and the right maternal? Or is it mixed?
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Not sure if I've got the question right, but no DNA test can determine which specific segments you get from which parent. The trick is to work it out for yourself preferably with one or both parents or a close relative. If you tell FTDNA how these people relate to you by where you place them in your DNA tree, your matches will start showing with blue pants or a pink dress. Then when you do an in common with check on a match, the majority should be one side or the other (given that you are showing a bit of Cornish you might find a few people who match on both sides).
Sorry if I didn't answer the question or if you knew all that.
And speaking of chromosome browsers, My Heritage launched theirs yesterday. You can view seven matches at a time (FTDNA only allows five) and you can download all the segments from all the matches - I've got 1800! - to a spreadsheet, which you can also do on FTDNA.
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Thanks once again Spike. I thought so but am hoping to be able to categorise
I am clicking through now. I cheated and started with the 197 nearest/distant relatives ( out of 1935) but otherwise its a long process.
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Yes it is. What I do is download all of my matches and my sisters in one hit and my father's. Then I copy the results onto one spreadsheet and work out which ones we have in common with him so the rest are maternal Cornwall or Scotland. I do the same for GEDmatch every day and I've started on MH. I have my mother's matches on a spreadsheet with over 15,000 matches - albeit several duplicates.
You're there ;). And yes, I need to get a life.