McCool Name Study - Y-DNA Candidates

Date: [unknown] [unknown]
Location: [unknown]
Surnames/tags: McCool McCoole

We've confirmed through Y-DNA testing there are at least six (and perhaps ten) unrelated McCool lines (on their direct paternal ancestry from son to father to grandfather...). Many McCool descendants are interested in determining which line is theirs - and to learn more about that line.

Unfortunately, we have only about 25 McCool Y-DNA tests in the entire world. We hope to double that number (to 50) in 2023 - and double it again (to 100) in 2024.

Contents 1 Why do we need Y-DNA tests? 2 Top Testing Priorities 3 Identify the Toberhead McCool Line 4 Differentiate County Donegal McCool Lines

Why do we need Y-DNA tests?

In many cases, early McCool genealogy paper trails either don't exist or are inconclusive. For example, we may know that an ancestor Samuel McCool was the son of a John McCool - but we don't know which John McCool was his father. It appears that some of the assumptions made by early researchers were incorrect.

Any male McCool who matches on a Y-DNA test to another male McCool is proven to share a common male McCool ancestor. As we get additional matching Y-DNA tests (especially matching Big Y-700 tests), we can often pinpoint which McCool ancestor they most recently shared.

Top Testing Priorities

In all cases, the Y-DNA test must be taken by a male McCool who descends only from male McCools (back to the earliest known paternal line ancestor). Females don't inherit a Y chromosome.

While any Y-DNA test is helpful, we propose a testing strategy to try to build our understanding of as many McCool lines at the lowest overall cost. The tactics will vary depending on the existing documentation available for each family. Our initial plan is:

1) Attempt to get at least one Big Y-700 test from a male-line descendant of every male McCool born between about 1780 and 1820. By definition, that means we'll have a Big Y-700 test from a descendant one of his sons. 2) If that man has more than one son, try to get a Y-37 (or higher) test from a descendant of each of those other sons.

Identify the Toberhead McCool Line

Although a large percentage of American-born McCools believe they descend from John McCoole Sr (abt.1645-1719) who established Hillmount Farm in Toberhead, County Londonderry in the late 1600s, none of them can yet prove it.

Fortunately, John had multiple sons who are believed to have living male McCool descendants. If we can convince three to four key McCool men who descend from his sons (other than John Jr) to take a Big Y-700 test, we should be able to set this question to rest.

Differentiate County Donegal McCool Lines

We suspect that a significant percentage of McCool lines have ancestors who once lived in County Donegal. Minimal records exist about how those lines might (or might not) be related.

• Quebec / north Ontario McCool descendants: Michael McCool (abt.1780-1844) is believed to have had four sons. Ideally, we would like a Big Y-700 test from a male McCool descendant of each of those sons. We can settle for one Big Y-700 test from a descendant of one of his sons and a Y-37 test from a descendant from the other three.

• Walla Walla WA McCool descendants: a Big Y-700 test from a male McCool descendant of Hugh McCool (1856-1939) or James A McCool (1857-1902) - and a Y-37 test from a descendant of the other.