Author Topic: Is it better to have a higher CMs number or more segments!?  (Read 2330 times)

Offline Braytons

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Is it better to have a higher CMs number or more segments!?
« on: Thursday 22 November 18 13:21 GMT (UK) »
Hello

Please can anyone give me an idea, from their own experience of matches or their deep knowledge of dna, if its better to have a higher CMs number or more segments.

I have two or three matches on Ancestry, described as Very High or High.  One of which says 51CMs 1 segment and another which says 49CMs over 3 segments. 

I have not been able to find a match with my tree with either of them despite hours of creating mirror trees.

I am hoping they may be a link to my Grandmother who I believe was adopted.

Cheers
Braytons

Offline sugarfizzle

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #1 on: Thursday 22 November 18 16:16 GMT (UK) »
Both are valid matches, I don't know if one is better than the other as such.

Ancestry puts them in total cM order, I have  matches at 55/6, 52/2, 49/5, 43/3, 42/4.

They are in order 3rd cousin once removed, 3rd cousin once removed, 3rd cousin, 5th cousin, 3rd cousin.

Hope this helps!

Regards Margaret
STEER, mainly Surrey, Kent; PINNOCKS/HAINES, Gosport, Hants; BARKER, mainly Broadwater, Sussex; Gosport, Hampshire; LAVERSUCH, Micheldever, Hampshire; WESTALL, London, Reading, Berks; HYDE, Croydon, Surrey; BRIGDEN, Hadlow, Kent and London; TUTHILL/STEPHENS, London
WILKINSON, Leeds, Yorkshire and Liverpool; WILLIAMSON, Liverpool; BEARE, Yeovil, Somerset; ALLEN, Kent and London; GORST, Liverpool; HOYLE, mainly Leeds, Yorkshire

Census Information is Crown Copyright, from www.nationalarchives.go

Offline Mart 'n' Al

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #2 on: Thursday 22 November 18 16:18 GMT (UK) »
I have wondered this, and having read a lot have still never found an answer. I even wonder if I started a rootschat thread on this some months ago.

Martin

Offline Braytons

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #3 on: Thursday 22 November 18 19:47 GMT (UK) »
Thank you both Margaret and Martin for your replies. 

Margaret do you mean you have you been able to trace how these matches you mention are related?  I admit I have yet to fully grasp how "removed" works in relation to cousins.

Martin, yes after I asked the question I thought about how Ancestry list them in order of CMs and maybe that should be a clue.

In my quest for my Grandmother's origins I am wondering if I am kidding myself that I will be able to find her mother/father.  By definition there is no paper records so it could be literally anyone!

Braytons


Offline mgeneas

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #4 on: Thursday 22 November 18 20:04 GMT (UK) »
My daughter in law has found both of her unknown grandfathers through dna. Luckily descendants of both had tested.

Offline brigidmac

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #5 on: Thursday 22 November 18 20:29 GMT (UK) »
My grandmother was informally adopted ...luckily we had a paper trail but the DNA did throw up a 2nd cousin to my mother who was actually  a half cousin they shared a grandmother not a grandfather ...also 3rd and 4th cousins in America with no obvious name links were connected to grandmas birth father .

You have to work on a process of elimination ....look at place of origins of shared matches if a specific village or region keeps cropping up it could be significant     

Also eliminate the links that are through your birth parents and known grandparents and maybe the 3rd cousins not connected will give clues to  who your grandmothers parents were

Good luck .

Any chance she was adopted by a family member ? What year are we talking about ?
Roberts,Fellman.Macdermid smith jones,Bloch,Irvine,Hallis Stevenson

Offline Mart 'n' Al

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #6 on: Thursday 22 November 18 20:31 GMT (UK) »
I found my earlier posting to which I referred.

https://www.rootschat.com/forum/index.php?topic=796843.msg6537777#msg6537777

This will also help:

https://isogg.org/wiki/CentiMorgan

Finally, on

genie1.com

"Regarding the 'largest cM', generally, the larger the biggest individual segment, the closer the relationship."

Martin

Offline sugarfizzle

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #7 on: Thursday 22 November 18 20:39 GMT (UK) »
Thank you both Margaret and Martin for your replies. 

Margaret do you mean you have you been able to trace how these matches you mention are related?  I admit I have yet to fully grasp how "removed" works in relation to cousins.

In my quest for my Grandmother's origins I am wondering if I am kidding myself that I will be able to find her mother/father.  By definition there is no paper records so it could be literally anyone!

Braytons

These are confirmed matches, sharing as follows -

55/6, my 3G grandparents, her 2G grandparents, I am the 'removed'
52/2, my 2G grandparents, his 3G grandparents, he is the 'removed'
49/5, joint 2G grandparents
43/3, joint 4G grandparents
42/4, joint 2G grandparents

Descendants of your missing great grandparents would be your 2nd cousins if the same generation as you, or 2nd cousins removed.
51CMs 1 segment and 49CMs over 3 segments are approx what I have detailed above - you can see the discrepancies between the DNA shared, especially with the 5th cousin.

But at this level it is reasonable to say that the matches are valid and indeed Very high or High.

For cousin calculator try one or both of these -

http://www.cousincountry.com/site/cpage.asp?cpage_id=180010891&sec_id=180004334

http://www.cousincountry.com/home/180004334/180004334/Cousin%20Chart%20Snippet%202.jpg

Regards Margaret
STEER, mainly Surrey, Kent; PINNOCKS/HAINES, Gosport, Hants; BARKER, mainly Broadwater, Sussex; Gosport, Hampshire; LAVERSUCH, Micheldever, Hampshire; WESTALL, London, Reading, Berks; HYDE, Croydon, Surrey; BRIGDEN, Hadlow, Kent and London; TUTHILL/STEPHENS, London
WILKINSON, Leeds, Yorkshire and Liverpool; WILLIAMSON, Liverpool; BEARE, Yeovil, Somerset; ALLEN, Kent and London; GORST, Liverpool; HOYLE, mainly Leeds, Yorkshire

Census Information is Crown Copyright, from www.nationalarchives.go

Offline Braytons

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Re: Is it better to have a higher CMs number or more segments!?
« Reply #8 on: Thursday 22 November 18 22:11 GMT (UK) »
Wow, it will take me a few hours to digest all your replies and its late now so will leave it till tomorrow. 

In the mean time, thank you so much everyone for your replies and help.

Cheers
Braytons