Comments on Thomas Davis

Question

On 28 Jan 2024 Daryl Davis wrote on Davis-1090:

My name is Daryl Davis and I have taken the big 700 Y-DNA test. My results are backed up with documentation to a common ancestor with two other testers (both tester have taken a Y-111 DNA test). I have a two step genetic distance with a common ancestor of Moses Davis (1657-1724 Oyster River, N.H. ) and a five step genetic distance with a common ancestor of John Davis ( about 1550-1626 Acton-Turville South Gloucestershire England.) Also I have one step genetic distance with an unknown common ancestor about 1750. Again this other tester did a Y-111 DNA test. I did a SAPP test comparing my DNA STRs with The proposed descendants of Thomas Davis (1603-1683). The best results of the seven testers compared to mine was an eighteen step genetic distance. This would put a common ancestor hundreds of years before John Davis of Acton Turville. My opinion is that the DNA of the proposed ancestors of Thomas Davis son of John Davis is proven that they are not descendants of that Thomas Davis.

Answer 1

Clearly the proposed descendant of Thomas Davis (1603-1683) is not descended from John Davis (1562-1626), but the question is where is the line broken?

You mention 'a descendant' and 'seven testers', so I am not clear if there are multiple descendants of Thomas Davis involved. 

If there are seven of them, then who is their documented most recent common ancestor and are their genetic distances compatible with that? The line from that ancestor to John Davis has a break in it, but the specific father-son relationship between John and Thomas is only disproved if the MRCA of the seven is Thomas.

If there is only one tester, then the break in the line could be in any generation between John Davis and the tester.

Comments

www.familytreedna.com/public/Davis?frame=ycolorized

Davis/Davies/David - Y-DNA Colorized Chart

Grouped under

John Davis of Newbury, Mass.

Kit # Real kit numbers removed for security reasons

Male 1 Y-67 John/Thomas Davis Essex Co Ma 1635 England R-M269

Male 2 Y-37 Edward Davis b 1757 d 1807 MA CT Unknown Origin R-M269

Male 3 Y-25 Cornelius Davis, MA. United Kingdom R-M269

Male 4 Y-25 John/Thomas Davis Essex Co MA 1635 England R-M269

Male 5 Y-37 Thomas Davis b1603 - Haverhill, MA United Kingdom R-M269

Male 6 Y-37 John/Thomas Davis Essex Co MA 1635 England R-M269

Male 7 Y-67 adopted Unknown Origin R-M269

The above are the proposed descendants of Thomas Davis that I ran a SAPP test on to compare our STRs

SAPP test genetic distance with myself and two of the Y-67 testers

                      Myself Y-111    Male 1 Y-67        Male 2 Y-67

Myself Y-111      111                    22 GD                  18 GD

Male 1 Y-67       22 GD                 67                       4 GD

Male 7 Y-67       18 GD                 4 GD                    67

If you belong to FamilytreeDNA you can view the Davis/Davies/David at the above web site

---

The problem with these results is that they report the most distant known ancestor, not the most recent common ancestor. You cannot tell from the public results whether they all descend from different sons of Thomas, or some other permutation such as they all descend from one great-great-grandson. Without their genealogies it is impossible to tell which generations of the paper trail are confirmed by the DNA and which might be the one where the paper trail is wrong.

Answer 2

Daryl,

From what I have been repeatedly told once you have the Big Y700 like you have the STR's really no loner matter as much as SNP's do. With that said you are comparing your Big Y700 to lesser tests so you will miss out on information especially Y-67 and down. What you are describing definitely leads down the path of questionable lines of descent. I am actually in the same boat but with a different surname. I look forward to seeing if you get it worked out.