Monday, May 3, 2021

Researcher Beware - Sometimes the AncestryDNA ThruLines Are Wrong

 I receive very few NEW AncestryDNA thruLines these days - occasionally one a week.  But I check each one out.  I now have about 430 of them.  

1)  I received a new one last week, with the common ancestors of my so-called "Potential Ancestors" 5th great-grandparents Johannes Rowe and Catherine Loescher.  The Rau/Rowe and Loescher families of New York were Palatines from Germany and the families are in the Henry Z. Jones Palatine Families of New York book).

My genealogical research has found no evidence that they are the parents of my 4th great-grandfather, Philip Rowe (1752-1817) of Hunterdon county, New Jersey, but many online family trees at and other sites show Philip Jacob Row as the son of Johannes and Catherine (Loescher) Rowe (or Row or Rau or Rauh) of Dutchess County, New York.  

2)  I looked at my list of ThruLines and saw that Johannes Wilhelmus Rowe and Catherine Loescher had a new descendant and a purported 6th cousin with me - but only at the 13 cM level.  Here is the top of the ThruLines chart:

You can see my ThruLine through Philip Row to me on the left, which I think is wrong.  The ThruLine on the right through Anna Maria Rowe is probably correct - it has Anna Maria born in Dutchess County, New York and that line goes to Vermont and is pretty well sourced.

The middle ThruLine is the new one, and it goes through a Mary Ann Rowe (1760-1825).  

There are a number of Ancestry Member Trees that include this person - the first one is the only tree with an attached record.  I clicked on that tree and then on the profile for Anna Maria Row and saw:

This Anna Maria Rowe was born in Cornwall, England, and died in Cornwall in 1825.  She had children with an unknown man and had three Lamerton children in Cornwall between 1792 and 1797.  The ThruLine shows that the line to the DNA match goes through Cornwall and into Devon.  The mother of my DNA match was born in Devon in England.  My DNA match was very likely born in Devon, England.

3)  I noted that this specific DNA match does not have a link to the Rowe/Loescher family in New York - so her tree does not have the wrong connection to the colonial New York couple.  However, AncestryDNA does have the connection because of similar names and/or family tree(s) with an error.  That's the problem with BIG family trees (I keep saying that Ancestry uses a BIG family tree that they use for ThruLines).  I noted that FamilySearch Family Tree has my Philip Row (1752-1817) of New Jersey conflated with several sets of parents and several spouses with children also.  "Pobody's nerfect" (not even me!) in the family tree world!  

What are the chances that a young lady of German heritage born in 1760 would move to Cornwall in England before about 1790 and marry a man and have children there?  I will take bets at 100 to 1.  

So this AncestryDNA ThruLine is wrong in my humble opinion.  

4)  But wait - I share 13 cM in 1 segment with this DNA match.  I may be a distant cousin (that is nominally a 4th cousin relationship), but it may be a segment on a chromosome that is common to many people of English ancestry and we aren't really about 4th cousins.  Unfortunately, my DNA match's tree doesn't have many leaves on the pedigree chart so I can't easily work back to her 3rd to 6th great-grandparents to see if we share Somerset or Wiltshire families.  My guess is that we share a Somerset family related to my Vaux line in South Petherton, Somerset.

5)  The bottom line here is "You have to evaluate each ThruLine you have for the genealogy part of it, and ask critical questions like 'are there records that show each generational link?' and 'does this make sense time-wise and locality-wise?'"  


Disclosure: I have a complimentary all-access subscription from, for which I am thankful. has provided material considerations for travel expenses to meetings, and has hosted events and meals that I have attended in Salt Lake City, in past years.

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Marshall said...

> Sometimes the AncestryDNA Thrulines are wrong

Oh, yes. And sometime they change. and change back. And change again.

I have a DNA match who ancestry claimed that I had a "common Ancestor" with.
The next day, no common ancestor.
The following week - common ancestor.
Two weeks later - no common ancestor.

Maybe they were updating their tree all this time, and that was causing Ancestry to re-evaluate the relationship over and over.
but if so, they were doing so without adding or deleting people (the number of people in the tree did not change).

Bill said...


Thanks for this, agree every thruline needs confirmation. I find most are correct but a number are not.

You started this by saying "I receive very few NEW AncestryDNA thruLines...". Is there a notification system or is this via manual check.

Bill Greggs

Randy Seaver said...


There is a notification system for new ThruLines on the AncestryDNA ThruLines page under settings - it will tell you how many new ones you have for some time period.

I daily check for new "common ancestors" on the DNA Match page by clicking on "Unviewed" and then on "Common Ancestors." New ThruLines will appear there.

Because AncestryDNA updates ThruLines on a regular basis (perhaps even weekly?) a DNA Match may suddenly have a ThruLine. So I scan the list of DNA matches with a "Common Ancestor" every month or so and invariably find one or two that I either missed before or has shown up after a ThruLines update. I have about 428 right now.

Marshall said...

> I daily check for new "common ancestors" on the DNA Match page by clicking on "Unviewed" and then on "Common Ancestors." New ThruLines will appear there.

I do that every day.
Here are my totals for this year:
* January: 5 new matches
* February: 2 new matches
* March: 1 new match
* April: 1 new match
* May: No new matches so far.