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Old 10th October 2011, 04:57 PM
shandy4473 shandy4473 is offline
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Smile 3rd Cousin Match - Is My Great-Grandmother a sibling or cousin (Corrected Version)

Good Day Everyone,

I have a question to ask. I have a match to BOTH my father and his mother (my paternal grandmother) to a person that FTNDA states is a 3rd cousin to BOTH my dad and grandmother. This match has the following data: (For identity protection - let's call the match - Susie B)

Susie B Matched To Grandmother
Shared cM - 65.13
Longest Block - 42.96

Susie B Matched to Father
Shared cM - 62.02
Longest Block - 42.96

Goal
I am trying to determine if my grandmother's mother - Addie Ruth Johnson - is a full cousin or half sibling to the relatives of the household that she was living in the 1900 census.


Current Evidence
Based on traditional family knowledge - Addie Ruth Johnson and her relative - Louis Johnson - are supposedly half siblings. I know from the paper trail - my great-grandmother (Addie Ruth) is a half relative in that her father was different from Louis's father. Addie Ruth and Louis are suppose to have the same mother, BUT the paper trail says the mother of Louis is someone else. I am thinking that Louis's father and Ruth's mother are brother and sister - which would make Louis and Addie Ruth cousins.

The male Johnson ancestor of the Susie B would be an uncle to my great-grandmother - Addie Ruth and Louis. Susie B's grandfather would be a cousin to Addie Ruth.

Question
Can it factually be determined whether Ruth and Louis are full/half cousins or half siblings from Susie B's DNA matching data or would I need to DNA test a child or grandchild of Louis to compare to my grandmother's DNA profile?



Thoughts please.

Thanks
Steve

Last edited by shandy4473; 10th October 2011 at 05:06 PM.
  #2  
Old 12th October 2011, 09:41 AM
mkdexter mkdexter is offline
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Those numbers (where a person matches mother and son by about the same amount) are normal results once the DNA connection is that far back.

You can't use sums at that point. You will need addition information/testing of other persons in your tree.

Matt.
  #3  
Old 12th October 2011, 12:35 PM
shandy4473 shandy4473 is offline
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Smile Thanks

Thanks MKDexter. One important discovery I have made is that my 2nd great-grandmother - Valada Johnson - who was Addie Ruth's mother - definitely was NOT a Johnson by marriage!!!! In order for Susie B, my dad, and paternal grandmother to share DNA, Valada must have been a Johnson by relations as the shared DNA clearly came from shared common Johnson ancestor through her.

Last edited by shandy4473; 12th October 2011 at 12:38 PM.
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Old 12th October 2011, 12:59 PM
Geneadict Geneadict is offline
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You will need a more recent relative to provide either positive or negative validation of your question. Best bet is to get earliest living generation direct descendant of person you are trying to determine relationship with.

Beyond 2nd cousins, autosomal DNA share by itself can not predict relationship with a high degree of accuracy. Up to 2nd cousin, you can usually predict within one degree of relation. Recombination is random and any predicted relationship beyond these provided by either FTDNA or 23andMe is more likely distant.

For the example used, the fact that next generation has practically the same match as the prior actually suggests it may be more distant.
  #5  
Old 12th October 2011, 01:26 PM
shandy4473 shandy4473 is offline
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Smile A bit far indeed

Thanks Geneadict - I figured as much. Wanted to get a confirmation. I did discover that the earliest ancestor was not a Johnson by marriage due to the fact there was a DNA match with my grandmother and father.
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Old 12th October 2011, 02:14 PM
Geneadict Geneadict is offline
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If there is a living child of Louis to test, that is your best route.

You would be looking at either a 2nd cousin or half first cousin to your grandmother whom you have tested. At this distance the share may make a strong suggestion for one or the other, but if high for one relationship estimate, or low for the other may not be conclusive. Going a generation below this (2nd cousin once removed or half first cousin once removed) would have higher likelihood of being less conclusive. Testing of additional known cousins at various genetic distance could help provide certainty.

Assuming that the other (presumed unrelated) parents of Louis and your great grandmother were in fact not closely related, you should be able to prove the relationship. If the other parents were related or if the related parents had multiple relationships (i.e. grandparents being related, etc), this could make it more difficult to prove anything with certainty.
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Old 12th October 2011, 02:22 PM
Geneadict Geneadict is offline
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Quote:
Originally Posted by shandy4473 View Post
Thanks MKDexter. One important discovery I have made is that my 2nd great-grandmother - Valada Johnson - who was Addie Ruth's mother - definitely was NOT a Johnson by marriage!!!! In order for Susie B, my dad, and paternal grandmother to share DNA, Valada must have been a Johnson by relations as the shared DNA clearly came from shared common Johnson ancestor through her.
Can you share details of your findings on this? What info do you have to prove the DNA share that your father and grandmother have with Susie came via one of your great grandparents as compared to the other? or via any of the other 3 grandparents of your grandmother (i.e your 2nd great grandparents) rather than Valada?
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Old 12th October 2011, 02:39 PM
shandy4473 shandy4473 is offline
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Smile More detailed information

Quote:
Originally Posted by Geneadict View Post
Can you share details of your findings on this? What info do you have to prove the DNA share that your father and grandmother have with Susie came via one of your great grandparents as compared to the other? or via any of the other 3 grandparents of your grandmother (i.e your 2nd great grandparents) rather than Valada?
Sure Geneadict - For identity protection let's call Susie B's grandfather S. Banks. S Banks's mother (S. Henderson) married a Johnson as the 1900 census shows and had two children - Crate and Boysie. This was before S. Banks was born. The Johnson was an Albert Johnson - who was an uncle (great uncle more accurate) of my grandmother.

Addie Ruth's father was a Hardeman (known through Ruth's death cert and family knowledge) and mother - Valada Johnson. In order for my grandmother and Susie B to share DNA, Valada Johnson must have been a Johnson by birth as Valada and Albert both have a common ancestor they received the shared DNA from. That shared DNA was passed to my grandmother (via her mother Addie Ruth) and to Susie B (via S Banks).

Of course S Banks may have NOT have been Susie B's granddad (Crate or Boyse may have been) but that's irrelevant from my point on Valada being a Johnson and NOT by marriage.

Steve

Last edited by shandy4473; 12th October 2011 at 02:44 PM.
  #9  
Old 12th October 2011, 02:50 PM
shandy4473 shandy4473 is offline
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Smile

Quote:
Originally Posted by Geneadict View Post
If there is a living child of Louis to test, that is your best route.

You would be looking at either a 2nd cousin or half first cousin to your grandmother whom you have tested. At this distance the share may make a strong suggestion for one or the other, but if high for one relationship estimate, or low for the other may not be conclusive. Going a generation below this (2nd cousin once removed or half first cousin once removed) would have higher likelihood of being less conclusive. Testing of additional known cousins at various genetic distance could help provide certainty.

Assuming that the other (presumed unrelated) parents of Louis and your great grandmother were in fact not closely related, you should be able to prove the relationship. If the other parents were related or if the related parents had multiple relationships (i.e. grandparents being related, etc), this could make it more difficult to prove anything with certainty.
Louis had at least 17 kids. Some of Louis's grand kids are living. The traditional belief is that Louis and Addie Ruth had the same mother but that's not likely true due to the fact I found Louis's death record. The death record stated that Louis's mother was not Valada Johnson but Savannah Lewis.

I assume a DNA test of one of Louis's grand children to my grandmother would shed some light. It's likely Valada and Louis were brother and sister making Addie Ruth a niece to Louis. Or Valada and Louis's father were brother and sister - which would make Addie Ruth and Louis cousins!!!
  #10  
Old 13th October 2011, 12:04 PM
Geneadict Geneadict is offline
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ok, let me see if I'm following this correctly, along with a few questions:

1) You have a fairly recent confirmed paper trial tie between Susie B and your grandmother - namely the Albert Johnson that you mentioned - but unclear whether the genetic tie is through him. Are you saying he is father of Susie's grandfather S. Banks, or just another spouse of his mother's?

2) By identifying Albert Johnson as your grandmother's great uncle, that implies you already know your grandmother's parents and grandparents in order to make this connection, so would already know whether she were a Johnson by marriage or not? Or is there something more to this?

3) We know your father's DNA share with Susie was inherited from your grandmother. We do not know for sure whether she got it from her father (Hardeman (or maybe Johnson if other things are unclear)) or her mother (Valda)(who could have been married to a Johnson then widowed and had child of Hardeman?) Do you have anything besides census records and death certificates to help you with the relationships you are attempting to validate?

4) Are all of Susie's ancestral lines traced back far enough (say 8-10 generations) to eliminate any of her other ancestors as being the source of the common DNA? If S Banks was the son of Albert Johnson, then making any connection from Susie to Albert would seem to be very dependent on whether S Banks was Susie's granddad or not (which you're calling irrelevant). If not, how could there be connection to Albert Johnson?

5) How is Savannah Lewis related to everyone else in the picture? Any record of her marrying a Johnson?

6) Ever consider that one or more of the death certificates contained incorrect info, which happened allot depending on what the informant actually knew so long after the actual birth event took place? Being death certificates are more distant from the birth event than almost any other documentation, it should be considered secondary to any other documentation from closer to the birth event (if there is any).

We can take this offline if you prefer not to put allot more details in the forum.

email: pw0909@gmail.com

thks
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