31 Mar 2025

The MacDougall DNA Project at FamilyTreeDNA (FTDNA) currently has over 450 participants.

Of these, we have 93 men who have presently tested positive for YP326, a noteworthy marker on the R1a “Scandinavian” branch of the Y-chromosome tree. YP326 is considered to be the marker for individuals who are descended from Somhairle MacGillebride, AKA Somerled (https://en.wikipedia.org/wiki/Somerled). The significant prevalence of YP326 among Scandinavian, Icelandic, and Western Isles Scotsmen strongly supports the view that Somerled’s paternal line was Scandinavian.

61 of these R1a 93 project members are also positive for a descendant mutation of YP326, called YP5543 which is now known to be the signature marker of men who are paternal descendants of Dougal of Argyll and Lorn, eldest son of Somerled and Ragnhild Olafsdottir, and the progenitor of Clan MacDougall.

In addition, the project has around 300 members who are positive for R-M269, which is a significant marker on the R1b branch of the Y-chromosome tree. The R1b branch is more “Celtic” in nature and very common among Scottish and Irish men. Within R-M269 MacDougall members we see about 40 distinct groupings including groups of MacDougall men who share a paternal ancestry in Perthshire, Stirlingshire, Roxburgh and Argyll and Western Isles (incl. Mull, Jura, Barra, and Easdale). About a dozen of these R-M269 men are Dowell or McDowell men. So far we have not found any McDowell men who are positive for the YP5543 marker.

We also have around 40 MacDougall participants who are positive for I-M223, I-M253, and J-M172 which are SNP’s that are a little less common in England and Ireland.

Beyond these 400 or so MacDougall participants we have a further 80 or so project members who have no known MacDougall connection on their paternal line. It may be that some are connected to MacDougalls through other family members.

We are often asked how MacDougall men who are not positive for YP5543 got their MacDougall surname. The answer lies largely in the patronymic naming system that was used in parts of Scotland until the early 18th century whereby children would take their family name from the first name of the father – hence, young Hamish who was the son of Donald, would be referred to as Hamish MacDonald … where mac or mc (there is no difference) means son of, and sometimes also adorned with a “modifier” like Mor (big), Og (young), Ruadh (red-head) etc. The Scottish feudal and clan systems also meant that many tenants of clan territories, or subordinate vassals might take the name of their clan leader or superior a their own, often as a mark of respect. This is before we even consider name changes through adoption or illegitimacy. Accordingly, surnames can be a poor predictor of paternal lineage in Scotland.

Another frequent question is: “Are MacDougall men who do not have the YP5543 marker still able to be members of Clan MacDougall?” The answer is an emphatic YES. Every Scottish clan is comprised of men who can claim descent from the chiefly family, as well as men and women who are / were related to MacDougall family, and people who came by their MacDougall name through other means. Ours is an inclusive clan and we can all proudly proclaim our allegiance, wear our colors, and celebrate our heritage!!

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