Irish surnames and Y-DNA

Both Y-DNA and surnames are handed down from father to son, so can links be found between the two? The Irish adopted hereditary surnames earlier than the rest of Europe, in general, with some appearing in the early 10th century AD, though most were created during the 11th and 12th centuries. Previously standard Gaelic naming was predominantly genealogical. A man would be identified as X mac (son of) Y, or X ua (grandson or descendant of) Y, which became simplified to Ó. For example O’Brien meant grandson/descendent of Brian. Surnames in the form O’Brien could easily be passed down to the next generation, becoming inherited surnames. In time the Mac forms were also handed down. The Anglo-Norman conquest of Ireland from 1170 onwards brought in new surnames. It also led eventually to the decline of spoken Gaelic. Many Irish surnames were haphazardly and inconsistently converted to English language forms. In some counties this was enforced.1E. MacLysaght, Irish Families: their names, arms and origins (1985).

However the exceptional age of Irish surnames opens up exciting possibilities for tracing links with haplogroups. Men bearing the two most common Irish names, Murphy and Kelly, fall into multiple patrilineal lineages genetically. The surnames were formed from common personal names, which would be found in many families. However other surnames, such as Ryan, O’Sullivan, O’Neill, Byrne and Kennedy, show one predominant Y-chromosome pattern, as we would expect if they descend from a single ancestor. All of these fall within the most common Y-DNA haplogroup in Ireland, and indeed in Western Europe generally: R1b-M269. The surnames McCarthy, McGuinness, Donohoe and McEvoy show evidence of several founders.2B. McEvoy and D.G. Bradley, Y-chromosomes and the extent of patrilineal ancestry in Irish surnames, Human Genetics, vol. 119 (March 2006), pp. 212-9.

The predominance of R1b-M269 means that most Irishmen need to discover to which subclade of R1b-M269 they belong, before they can hope to see if they fit into the pattern for a particular surname. Indeed it is necessary to test down to the finest twigs of the tree. It has taken years for research to arrive at the point where matches can be detected between a particular surname and a particular SNP, as in the examples below. Earlier studies depended upon variation in STRs, which is a less reliable method.

Uí Néill

Irish peoples and polities c.800 AD.  Click to enlarge in new windowEarly attempts at linking haplogroup and Irish surname were over-hasty in their conclusions. The Y-DNA haplogroup R1b-M222 was initially thought to mark the descendants of Niall of the Nine Hostages. It is carried by nearly 20% of the men in Donegal today. In early historic times this was the territory of the northern Uí Néill, presumed descendants of the fabled 5th-century warlord. R1b-M222 is particularly common among those with some purported Uí Néill surnames such as Gallagher, Boyle, Doherty and O’Donnell, though not most of the O'Neills themselves. It also appears among the Connachta, supposed descendants of the brothers of Niall.3L.T. Moore, B. McEvoy et al., A Y-Chromosome Signature of Hegemony in Gaelic Ireland, The American Journal of Human Genetics, vol. 78, no. 2 (1 February 2006), pp. 334-338; E.B. O’Neill and J.D. McLaughlin, Insights into the O’Neills of Ireland from DNA testing, Journal of Genetic Genealogy, vol. 2, no.2 (Fall, 2006), pp. 18-26 . However wider testing has revealed that Donegal is not the hotspot for R1b-M222. The highest concentrations have been found in Belfast, in North-Eastern Ireland (44%), and Mayo in Western Ireland (43%). The figure for the latter may be unreliable, as there were only 16 men sampled from Mayo, but these new figures do suggest that the distribution map drawn from early testing needs to be revised. Outside Ireland there are roughly 10% of men carrying M222 in Northern England (Yorkshire), Western Scotland (Skye) and North-Eastern Scotland (Moray).4G.B.J. Busby, The peopling of Europe and the cautionary tale of Y chromosome lineage R-M269, Proceedings of the Royal Society B: Biological Sciences, Published online before print, August 24, 2011; N.M Myres et al., A major Y-chromosome haplogroup R1b Holocene era founder effect in Central and Western Europe, European Journal of Human Genetics, (advance online publication 25 August 2010).

Though migration from Ireland could account for some of the British M222, the pattern is unexpected for radiation from Ireland. So M222 is more likely to be a La Tène marker, spread from Northern Britain into Northern Ireland around 200 BC. If so it would be present among the people of north-western Ireland centuries before the Uí Néill came on the scene - if they actually did. Brian Lacey has sifted the political propaganda from the history. He shows that the Cenél Conaill (Cannon, Boyle, Doherty, Gallagher, McMenamin, O’Donnell) and Cenél nEógain (Devlin, Donnelly, Gormley, McLoughlin, O’Kane, Quinn) peoples claiming to be Northern Uí Néill were probably locals who had adopted that designation to link themselves with the incoming elite.5B. Lacey, Cenél Conaill and the Donegal Kingdoms, AD 500 – 800 (Dublin, 2006).

Percentages of R-M222 in European samples, arranged by percentage

Percentage Country Region Place n6Total number in the sample. Study
0.444 Ireland North Belfast 72 Busby et al 2011
0.438 Ireland West Ballinrobe, Co. Mayo 16 Myres et al 2010
0.269 Ireland West Galway, Co. Galway 67 Busby et al 2011
0.250 Ireland East Virginia, co. Cavan 16 Myres et al 2010
0.2157This figure is for the IMH 17-marker haplotype which was subsequently found to link to M222 (including one-repeat unit derivatives). Ireland NW Donegal ? Moore et al 2006
0.195 Ireland East Dublin 149 Busby et al 2011
0.143 Ireland North Near Magherafelt, co. Londonderry/Derry 21 Myres et al 2010
0.143 Scotland West Near Lochgilphead, Argyll and Bute 21 Busby et al 2011
0.112 Ireland South Bachelors Hill, Co. North Tipperary 89 Busby et al 2011
0.106 England NW Leeds, Yorkshire 47 Myres et al 2010 and Busby et al 2011
0.104 Scotland NE Nether Ringorm, Moray 67 Busby et al 2011
0.063 France 16 Myres et al 2010
0.063 Scotland NW Isle of Skye 80 Busby et al 2011
0.053 Germany 19 Myres et al 2010
0.045 Ireland SW Near Newmarket, Co. Cork 22 Myres et al 2010
0.042 Ireland South Carlow, Co. Carlow 24 Myres et al 2010
0.042 Wales North Abergele, Conwy 120 Busby et al 2011
0.040 England Central Lutterworth, Leicestershire 25 Myres et al 2010
0.019 England SE Gravesend, Kent 52 Myres et al 2010 and Busby et al 2011
0.014 Norway 138 Busby et al 2011
0.014 Sweden South Malmö 139 Myres et al 2010
0.012 France SW Toulouse 83 Busby et al 2011
0.009 Scotland Orkney 112 Busby et al 2011
0.0008Zero M222 was found in numerous other places in Europe that were sampled. These two places are selected simply because of the interest in possible routes to/from the Continent to British Isles. England SW Exeter, Devon 48 Myres et al 2010 and Busby et al 2011
0.000 France NW Rennes, Brittany 115 Busby et al 2011

Dalcassian surnames

There are interesting links emerging between subclades of R1b-L21 and Irish surnames related to two kindreds of Munster marked on the map above of Ireland c. 800 AD: the Dál Cais and Déisi Mumhan. The marker L226 defines what used to be known as the Irish Type III haplotype, linked to a group of Dalcassian surnames: O'Brien/Bryant, O'Casey, McCraw/McGraw/McGrath and O'Hogan. The Dál Cais or Dál gCais arose from obscurity among the peoples of Munster in the 7th and 8th centuries AD, when they pressed north into Thomond (now County Clare), expanding the territory of Munster. They claimed descent from Cas, 6th in descent of Cormac Cas, supposed King of Munster in the 3rd century AD. Whether or not the early parts of this pedigree are reliable, the O'Briens take their name from Brian Boru, High King of Ireland 926-1014, and the family were kings, princes and earls of Thomond until the 18th century.9D.M. Wright, A Set of Distinctive Marker Values Defines a Y-STR Signature for Gaelic Dalcassian Families, Journal of Genetic Genealogy, vol. 5, no. 1 (Spring 2009), pp. 1-7.

Déisi Mumhan

Another marker - L144 - has been found among men with surnames such as Whalen and Phelan, derived from the personal name Faeláin. Faeláin (wolf) occurs a number of times among the Irish royal houses. In fact two kings of that name died in the same year. The Annals of Ulster record the demise in 966 of Faelán son of Cormac, king of the Déisi of Mumu [Mumhan], and Faelán, king of Laigin. The descendants of the former appear in the same annals as Ua Faeláin by 1085,10The Annals of Ulster: Corpus of Electronic Texts Edition. a step towards surname development. So we can expect at least some Whalens and Phelans to descend from Faelán, King of the Déisi Mumhan, particularly those with origins in or near his former territory. The Déisi Mumhan then occupied what are now the Counties Waterford and Tipperary. A number of the Whalens and Phelans carrying L144 can trace their origins to Laois, Kilkenny or Waterford.11http://www.familytreedna.com/public/whalen/ Déisi simply means vassal peoples. But by the 8th century déisi communities in the south-east had formed the sub-kingdom of Déisi Mumhan (déisi of Munster). Naturally their elite promulgated the notion of the Déisi as an ancient tribe. In reality several unrelated kin-groups could have been united under that name. However the genetic marker L144 has also been found in men of the Welsh surname Prosser.12Michael Whalen personal communication. The surname Prosser clustered in South-East Wales by the 19th century: D. Hey, Family Names and Family History (2000), pp. 93-4. This may support the claim made in the Expulsion of the Déisi that one of the royal Déisi line Eochaid son of Artchorp went over the sea with his descendants to the territory of Demed. Philip Rance argues that they were recruited by the Late Roman authorities to protect Demetia (south-west Wales) from Irish raids. 13P. Rance, Attacotti, Déisi and Magnus Maximus: The Case for Irish Federates in Late Roman Britain, Britannia, vol. 32 (2001), pp. 243-270. Artchorp (Airtt Chirp) appears as an ancestor of Faeláin in an early pedigree.14Bodleian Library MS Rawlinson B 502, Corpus of Electronic Texts Edition, section 19, item 1365: http://www.ucc.ie/celt/online/G105003.html or M.A. O’ Brien, Corpus Genealogiarum Hiberniae, (Dublin, 1962), p. 253.

For information on many Irish surnames, see Ireland's History in Maps by Dennis Walsh.

Notes

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  1. E. MacLysaght, Irish Families: their names, arms and origins (1985).
  2. B. McEvoy and D.G. Bradley, Y-chromosomes and the extent of patrilineal ancestry in Irish surnames, Human Genetics, vol. 119 (March 2006), pp. 212-9.
  3. L.T. Moore, B.McEvoy et al., A Y-Chromosome Signature of Hegemony in Gaelic Ireland, The American Journal of Human Genetics, vol. 78, no. 2 (1 February 2006), pp. 334-338; E.B. O’Neill and J.D. McLaughlin, Insights into the O’Neills of Ireland from DNA testing, Journal of Genetic Genealogy, vol. 2, no.2 (Fall, 2006), pp. 18-26 .
  4. G.B.J. Busby, The peopling of Europe and the cautionary tale of Y chromosome lineage R-M269, Proceedings of the Royal Society B: Biological Sciences, Published online before print, August 24, 2011; N.M Myres et al., A major Y-chromosome haplogroup R1b Holocene era founder effect in Central and Western Europe, European Journal of Human Genetics, (advance online publication 25 August 2010).
  5. B. Lacey, Cenél Conaill and the Donegal Kingdoms, AD 500 – 800 (Dublin, 2006).
  6. Total number in the sample.
  7. This figure is for the IMH 17-marker haplotype which was subsequently found to link to M222 (including one-repeat unit derivatives).
  8. Zero M222 was found in numerous other places in Europe that were sampled. These two places are selected simply because of the interest in possible routes to/from the Continent to British Isles.
  9. D.M. Wright, A Set of Distinctive Marker Values Defines a Y-STR Signature for Gaelic Dalcassian Families, Journal of Genetic Genealogy, vol. 5, no. 1 (Spring 2009), pp. 1-7.
  10. The Annals of Ulster: Corpus of Electronic Texts Edition:http://www.ucc.ie/celt/published/T100001A/
  11. http://www.familytreedna.com/public/whalen/.
  12. Michael Whalen personal communication. The surname Prosser clustered in South-East Wales by the 19th century: D. Hey, Family Names and Family History (2000), pp. 93-4.
  13. P. Rance, Attacotti, Déisi and Magnus Maximus: The Case for Irish Federates in Late Roman Britain, Britannia, vol. 32 (2001), pp. 243-270; Michael Whalen personal communication.
  14. Genealogies from Rawlinson B 502,1365, Corpus of Electronic Texts Edition: http://www.ucc.ie/celt/online/G105003.html or M.A. O’ Brien, Corpus Genealogiarum Hiberniae, (Dublin, 1962), p. 253.