Ancestry ThruLines show how you may be related to your DNA matches. ThruLines suggests likely shared ancestors based on DNA test results and the information contained in Ancestry user trees – which are often inaccurate. As a result, relying on ThruLines to provide answers to your family history is an iffy proposition. Still, although Ancestry itself says “ThruLines don’t prove your specific connection to a DNA match,” ThruLines can prove very useful in filtering DNA matches that bear a closer look, and if you’re willing to put in the traditional research effort, ThruLines can provide support for – or against – a lineage.
Using an example from my own tree, I’ll illustrate the pitfalls of simply accepting ThruLines at face value, as well as how to use them effectively.
The question I am attempting to answer is whether Christian Fritts, 1724-1788, is the father of John Fritts (1766-c1850). A good paper trail exists for this line, but it gets a bit muddy – John’s first wife dies, he remarries to a woman named Mary, and suddenly there are two John and Mary Frittses in the same town at the same time, assorted other John Frittses in the area, sparse records in general, and nobody except the heads of household listed on the census.
Tip #1 – Test the oldest available generation.
The people we’re researching are pretty far back in time, but even if they weren’t – when using autosomal DNA, as Ancestry does, it’s important to remember that each generation gets only half of its DNA from each parent – so if you can go back even one generation, you have a little bit more to work with. For this example, I was able to use DNA from three relatives in the older generation – my mom, her sister, and one of their first cousins. Below are the results for my aunt, and at first glance, they look promising, right?
Not so fast.
To support the relationship, we need to show DNA matches to other documentable descendants of Christian Fritts – although there are 18 DNA matches to other descendants of John, they don’t tell us anything about the relationship between John and Christian. Here is what Ancestry suggests is the connection between Christian Fritts and the four DNA matches it suggests are descended from William (Wilhelm) Fritts. The dashed-line borders and green “evaluate” flags are a reminder that this is only a suggestion, based on Ancestry’s evaluation of the information in other people’s family trees.
Tip #2 – Don’t assume other people’s ancestry trees are correct.
The DNA matches to Wilhelm Fritts – all of them – are wrong.
Christian Fritts and his wife Elisabetha Waldorff had a son named Wilhelm – a baptism record shows this. And Wilhelm Fritts may or may not have had a son named William, I couldn’t say. But all of these DNA matches connect to Angelina Fritts, born 1845 in New York and later the wife of Henry Tupper – and she was not the daughter of this, or any other, William Fritts. Angelina, as it happens, is already in my tree, because she is the daughter of Robert Fritts, one of John’s sons.
Here is the marriage record of Angelina Fritts and Henry Tupper:
The marriage record is a transcription, and some errors are immediately apparent. The 1852 marriage date cannot be correct, as Angelina would have been seven years old – but the date of the certificate is 1862, and that is also the date that appears on the 1900 census record for Angelina and Henry Tupper. We correlate this marriage record with census records to confirm the rest of the information. Angelina’s father was Robert Fritts, and she appears in the Robert Fritts household on the 1850 census (with mother Maria Fritts) and 1860 census (with stepmother Ellen).
So, why are there four trees on Ancestry that claim Angelina is the daughter of William Fritts? The likeliest answer is the tendency of Ancestry beginners to copy other people’s trees and assume they are correct – one of the trees I looked that linked Angelina incorrectly to William, included the 1850 and 1860 censuses as sources – but Angelina was living in the Robert Fritts household, suggesting that researcher didn’t actually review the sources, or perhaps explained away conflicting evidence.
Since Angelina was documentably Robert’s daughter, and Robert was documentably John’s son, the DNA matches to Angelina Fritts’ descendants rightly belong in the John Fritts column – and we have no matches to descendants of William that we know of.
Tip #3 – Ancestry doesn’t make ThruLine suggestions for DNA matches that aren’t connected to a family tree.
There may be other DNA matches to Fritts descendants – even William – that help support our case, and they are simply not shown. If these matches have not built out their trees, Ancestry can’t make the connections; similarly, if their tree is incorrect, Ancestry’s algorithm may not be able to suggest a connection.
Ancestry appears to assume that other people’s trees are correct, but you should never make that assumption. Look at other people’s trees as clues, no more. If you can’t verify the information in the tree independently, dig deeper and see where the evidence actually goes. You might not even have to look very far – in the example above, there were two censuses that had the correct information attached to the incorrect trees!
But, what about the DNA and the ThruLines? Well, in this example, fortunately, there were matches to descendants of another of Christian Fritts’ children, his daughter Margaretha, and I was able to verify the accuracy of those connections with my own research – starting from the present (the DNA match) and working back in time to the point of connection (Margaretha Fritts, Christian’s daughter).
So, are Ancestry ThruLines accurate? Yes and no. ThruLines did correctly detect that descendants of Angelina Fritts are cousins, and placed them in the correct general family group. But, because the specifics were incorrect in Ancestry Member Trees, relying on ThruLines would have led to a false conclusion to the particular question we had asked.
But, if one uses Ancestry ThruLines as a clue as to what family group a DNA match belongs to, and does independent research to determine the exact connection, ThruLines can be an effective research resource – in spite of the drawbacks.