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ThruLines Analysis

Have you tested your DNA with Ancestry? If so, do you have a tree with at least a few ancestors named? And, are your DNA results attached to someone in your tree? Those are the requirements for Ancestry to begin populating your ancestral ‘ThruLines’.

Basically, ThruLines tries to locate other descendants of your ancestors and show relationships to a common ancestor. These suggested relationships are dependent on the accuracy of your tree as well as the accuracy of your DNA match’s tree.

Without evaluating those relationships, I believe one can use the number of matches an ancestor has to pick up clues about one’s tree. For example, my logic suggests that unless there are only children involved, the number of matches should increase from one generation to the next. I also believe that unless there are multiple marriages involved, the number of matches for the husband should match the number of matches for his wife. Thus, an analysis of the number of matches can raise questions about one’s own tree.

For example, I manage 4 tests on Ancestry. Three of those tests are for siblings. Thus when I see 2 matches for grandparents and 3 matches for great grandparents that suggests an issue.

However,, when I browse thru my matches, I find at least four known second cousins thru my ancestors Hiram Currey and Winnie Hutchinson that either don’t have a tree or have an unlinked tree. Spelling of the surname may also be an issue, since some records spell the surnames as Curry and Hutchison. Thus, I’m not overly concerned about their only being 3 matches for this pair of great grandparents.

These numbers can also reveal matches connecting thru a different spouse. My ancestor, Richmond Hammond had a daughter, Hattie, by his second wife. When I look at the number of ThruLines matches for Richmond Hammond and his first wife Sarah Ralston, they are not the same. Thus, this can be a clue to look for multiple marriages.

Another issue is revealed by comparing the number of matches between generations. For example, my 2nd great grandmother, Angelina Burke has 8 ThruLines matches. If I look at her parents, they also have 8 matches.

Since Angelina was not an only child, I would expect more matches for her parents than for her. Since that isn’t true, then I have to look at ‘why’. One reason might be that no one has tested from her siblings lines. Another reason my be that those descendants have tested but either don’t have a tree attached or have a very small tree that doesn’t have a person in common with my tree. It is also possible that other trees use a different format or spelling for the names of Henry Burke and Elizabeth Bland. Another reason is that my tree might be wrong. Thus, these numbers indicate that I need to do additional work on this particular line.

A telling issue is a very small number of matches for a distant relative. Thus, when I see only 2 matches for James Forbes while his wife, Ann Thomson has 16-19 matches, I know there is an issue.

Since I don’t have much data to support this ancestor, I’m assuming that I have a mistake in my tree.

And then there are the zeroes.

Even though these zeroes are associated with my mom’s 5th great grandparents, they are still a red flag that I likely have something wrong.

Thus, taking the time to record the number of matches for my ancestral ThruLines was worth it.

Below are the numbers for each of the ThruLines matches for the tests I manage: