Todd McKenna, a great-grandson of Thomas McKenna and Sarah Singleton, recently embarked on a journey of discovery through Y-DNA testing. He opted for the Big Y-DNA test, known for its thorough examination of the Y chromosome, which is passed down from father to son. This test allows for comparisons with others who have taken the same test, revealing potential paternal connections.

To Todd’s surprise, the results did not align with the expected McKenna lineage. Instead, the most probable paternal relatives were found to have the surname Sloan.  Thomas McKenna belongs to the haplogroup R-BY103024, shared with two other Big Y-DNA testers: Thomas Benjamin Sloan and Timothy Stewart. The earliest known male of this haplogroup was likely born around 1422 AD, while Thomas’ earliest paternal ancestor, Hugh McKenna, was born around 1777 AD. This suggests a non-paternity event (NPE) occurred between these two dates, leading to the McKenna surname.  A NPE occurs when the surname of a child is changed from the surname of the biological father.    A NPE could be an adoption, an illigitimate birth or where a husband dies and the wife remarries and a child changes their last name to that of the second husband.

In pursuit of further connections, Todd joined the Sloan Y-DNA Project on FamilyTree DNA. The project’s administrator identified two potential relatives, Jeffrey A. Sloan and Robert Edward Sloan, who had taken the Y-DNA67 test. However, the certainty of these matches is limited by the test’s scope, and a more definitive connection could be established if they underwent the Big Y-DNA test.

The intricate web of relationships and the historical journey of the McKenna family are explored in details within the Y-DNA Research Results.