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Irish DNA

A NEW history of the human colonisation of Ireland as revealed by commercial ancestral Y-DNA testing (UPDATED Oct 2021).

Modern commercial ancestral DNA testing is a truly remarkable tool. It provides a glimpse of the peoples who have contributed to our DNA  (autosomal DNA). It also allows one to track their direct maternal and paternal ancestral lines (mtDNA and Y-DNA respectively). The paternal ancestral line is much easier to track using commercial ancestral DNA testing (there is far less mtDNA, and the surname is not usually passed maternally). With Commercial Y-DNA testing one can literally reconstruct one's paternal ancestral journey over millennia! Irish Origenes has conducted hundreds of Y-DNA (paternal) Case Studies over the last 10 years. But what do they reveal about the peopling of Ireland?

Each Irish Origenes Y-DNA Case Study pinpoints an origin for the test subject’s direct male ancestor an estimated 1,000 years ago (when surnames first appeared). More distant genetic relatives and specific paternal genetic markers (Haplogroups) shed light on the ethnicity of each Case Studies paternal ancestors. For example, a male named ‘Doyle’ who takes a Y-DNA test discovers he matches lots of males named O’Toole, Byrne and Kavanagh; surnames that all arose among related males living in County Wexford (where an origin is pinpointed 1,000 years ago). Yet his more distant matches are dominated by surnames of Scandinavian origin and a R-M198 Haplogroup. That indicates that the test subject is descended from a Viking from Norway who settled in Southeast Ireland. You can download and study a sample of one of the hundreds of Y-DNA Case Studies detalied (click here).






But what do the Y-DNA Case Studies reveal about the peopling of Ireland? An examination of over 200 randomly selected Irish Origenes Y-DNA Case Studies reveals no evidence of a pre-historic ‘hunter gatherer’ input into the modern Irish population. The hunter gatherers that inhabited Ireland after the last Ice Age were never particularly numerous (estimated 10,000 at most) and appear to have been wiped out by the arrival of the first ‘Neolithic’ farmers who it is estimated began arriving in around 4,000 BC. Remarkable, 4% of Irish Origenes Y-DNA Case Studies are for males with a distinctive Neolithic (I-P37) DNA signature, and they are overwhelming associated with the western half of the island (with a tentative link along the course of the River Shannon in the west of Ireland). Irish Neolithic Y-DNA Case StudiesThat means that if you have a paternal ancestor born in Ireland, then there is a 4% chance you carry the I-P37 Y-DNA marker, and that you paternal ancestral line was present in Ireland continuously for nearly 6,000 years. It is estimated that the Neolithic population of Ireland may have peaked at about 200,000 inhabitants. But they were decimated and pushed west and into less favourable lands by the arrival of the first ‘Keltoi/Celtic’ people who poured into Britain and Ireland from the Rhine River Valley area of Central Europe from around 800BC onwards. Irish Brythonic Y-DNA Case Studies

The ‘Celtic’ inhabitants of what is now Britain and Ireland would become known as the ‘Ancient Britons’ (hence the ‘British Isles’). It is this Briton/Brythonic Y-DNA signature that dominates the genetic makeup of the Irish male, accounting for almost half of Irish Origenes Y-DNA Case Studies. However, the Brythonic Celtic Irish are not distributed evenly, although they completely dominate Southern Ireland, they are conspicuously absent from much of Northern Ireland. The language that the Brythonic Celts once spoke survives today as the Welsh language (the Brythonic DNA signature dominates Wales, Western England and much of the Scottish Lowlands). So why don’t Irish people speak Welsh?

Irish Gael Y-DNA Case StudiesBlame ‘Julius Caesar’ and his Conquest of Gaul. Caesar's Conquest of Gaul was truly devastating. Y-DNA Case Studies reveal that Gaulish refugees poured into Briton from around 50BC onwards. With the subsequent Roman invasions of Britain, Gaulish refugees sought refugee in remote corners of Scotland or made the short crossing in Ireland. Irish Origenes Y-DNA Case Studies reveal that at least 2 distinct groups of Gauls would settle permanently in Ireland, an R1b group who would settled in Donegal (‘base of the foreigners’) and would later give rise to the Irish Gael R-M222 marker, while another group  carrying the I-M223 marker would settle in Southeast Ulster. Today, approximately 36% of males with a paternal Irish origin will reveal a ‘Gaul/Gael’ Y-DNA signature. The Northern Gauls or Gaels would then battle the Southern Britons for control of the island (this north/south conflict is evident in Irish myths). However, it was the Gaels of the north who would come to dominate the language and culture of Ireland (why remains a mystery).

Irish Viking Y-DNA Case StudiesThe North Gael / South Briton division would have been evident to the Vikings who first set foot in Ireland in around 800AD, and who today account for approximately 2% of Irish Y-DNA Case studies. Surprisingly, the Y-DNA studies (to date) reveal a Norwegian origin for all Vikings, it also reveals that the Norwegian Vikings formed an alliance with the Northern Gaels, and that both raided and colonised together throughout much of Ireland.

Norman Viking Y-DNA Case StudiesIt would be a truly Gaelic Christian Ireland that the Normans would next attempt to conquer. They would come close, but what the Y-DNA reveals is that the Normans were a mix of genuine Normans (with Viking ancestry), but also Bretons, Flemish, English and Welshmen. Norman Y-DNA Case studies are trickier to identify, and although 12% of Irish people have Norman surnames, only 6% exhibit a Norman paternal origin. Gallowglass Y-DNA Case StudiesTo defeat the Normans, the Gaels would once again turn to Viking allies, particularly those of the Western Isles of Scotland. With the aid of these Scots-Gael ‘Gallowglass’ mercenaries they would role back the Norman advance. Today, about 1% of Irish males will exhibit a Scottish Gallowglass origin.

Ireland would remain the last bastion of a ‘Gaulish’ Europe until its final Conquest which began during the reign of Henry VIII. That Conquest would last 150 years and would drag the Gaels kicking and screaming into the modern European world (a Europe with an identity forged by their Roman nemesis). Today, the Gaulish language once spoken by Rome’s enemies survives in remote parts of Ireland and Scotland. If over 2,000 years ago, Julius Caesar had failed, and the Gauls had triumphed, it is quite possible that it would be Gaelic being spoken throughout Western Europe (but a dialect of modern Welsh in Ireland).

What will your DNA reveal? CLICK HERE for a FREE CONSULTATION on your DNA results (Y-DNA, Autosomal or mtDNA) or to find out which commercial ancestral DNA test is suitable for you. Remember folks, I am a trained Scientist with over 20 years’ experience in both Academic and Industrial Labs. Always check the scientific qualifications of the blogger offering DNA advice. An honorary qualification is no substitute for decades of genuine awards and practical experience.

English Origenes

Scottish Origenes