R-Z3000 is the DNA of men with surnames, such as McDonald, McGuire, McAuley, Boylan, Connolly, MacDougall, McMahon, Carroll, McQuillen, Monaghan, and McKenna, found in ancient genealogies of the Three Collas. The ancient genealogies record that the Three Collas lived in Ireland around 300 A.D., and their descendants have been kings, lords, chiefs, and saints down through the ages. The Three Collas conquered Ulster in the battle of Achadh Leithdheirg, by defeating the forces of King Fergus Foga at Emain Macha aroudn 330 A.D. The territory conquered by the three Collas comprised the present day counties of Louth, Monaghan, and Armagh. Colla da Chrioch was the founder and first King of the Kingdom of Oriel. Colla da Chrioch died about the year 357 AD. Many of the Clan Colla progeny were styled Kings of Oriel, down to the twelfth century. Since the Colla DNA signature would be passed down from father to son… a Y-chromosome test (67 markers) for male participants is required. There is no cost for joining additional projects at FTDNA, if you've already been tested at FTDNA. See the Background page for: - Important Information about Joining the Project - Clan Colla SNP Tree - What Defines Clan Colla DNA? - Testing Alternatives - Colla Subgroups - FTDNA Test Results - Project Administrators - Who Were the Three Collas?