South Irish R1b Y-DNA

The STR Markers

In February 2006, Dr. Ken Nordtvedt identified a cluster of people carrying a distinctive Y-DNA haplotype, centered (although not exclusively) in southern Ireland. It was tentatively named the "South Irish" haplotype of the R1b haplogroup.

He noted the cluster exhibited the following 7 STR marker values which differ from the Atlantic Modal Haplotype (AMH):
    391 = 10
    385b = 15
    439 = 11
    447 = 24
    456 = 15
    442 = 13
    635 = 24 (a.k.a. GATA-C4, a non-FTDNA marker)
The cluster also contained 4 other STR marker values which appear in much higher percentages than in the AMH [1]:
    390 = 24
    458 = 17
    449 = 29
    H4 = 11
Later review of extended FTDNA tests added one more distinguising marker:
    565 = 11

Dr. Nordtvedt also listed some of the surnames he found in the various databases (YSearch and SGMF) which matched these markers:
    Bryan, Burns, Clary, Donahue,
    Givens, Hayes, Irwin, O'Leary, McKenna, O'Shea, Reagan, Desmond,
    Hughey, Fitzgerald, O'Connor, McRay, O'Keefe, McLennan, Mihigan, Hennessey
    Towey, Sullivan, O'Kane, Coghlan, Allen, Seal, Kelly, Kenty
And then he asked the question, “Perhaps one of the list experts on Ireland and its surnames can see a pattern?”

It's A Geneological Cluster?

Some of the surnames were immediately familiar as names from the Eoganacht septs of Munster:
    Donahue, Hayes (i.e. O'Hea), O'Leary, O'Keefe, Sullivan, Coghlan
And these additional Eoganacht sunames were later identified in the databases:
    Callahan, Lynch, Healy, Dennehy, Crowley, Collins, Donovan

Many people carrying Eoganacht surnames have Y-DNA which matches the "South Irish" haplotype:
* An count (3/06) of the Trinity College study of Irish patrilineal ancestry showed that the 4 Eoganacht surnames tested (Donohoe, McCarthy, McGillycuddy, O'Sullivan) accounted for 64 of the 104 matches to the "South Irish" haplotype in the countrywide survey of 43 surnames.
* A review (2/06) of several Family Tree DNA projects found a good percentage of McCarthys (9 out of 31), Sullivans (16 out of 39) and O'Donoghues (15 out of 55) who appeared to fit into the cluster, including the officially recognised "O'Donoghue of the Glen".

[More information about the Eoganacht septs can be found here.]

It's a Geographic Cluster?

Even some of the non-Eoganacht surnames were clearly centered in Munster:
    Bryan, O'Shea, Reagan, Desmond, Fitzgerald, O'Connor, Mihigan, Hennessey

An important analysis that remains to be done would compare the percentage of the "South Irish" haplotype in Eoganacht surnames, with its percentage in non-Eoganacht surnames from Munster (i.e. Driscoll, O'Brien, O'Shea, Ryan). This would help clarify whether the cluster is a wider geographic one, or a narrower one specifically centered on the Eoganacht.

In early 2008, Trinity College Dublin published a paper which approached this subject. Unfortunately, the dataset was small and lacking many of the "South Irish" STR markers. More irritatingly, it made no mention of the already known "Irish Type 3" modal haplotype, which is likely a Dal Cais signature. It also made some questionable decisions about which surnames to count as Eoganacht.
With all those caveats,  the following samples matched the "South Irish" modal (allowing 1 mis-match on the markers 390=24, 391=10, 439=11, 385b=15):
247 total, 81 matched (33%)
152 Non-Eoganacht, 41 matched (27%)
95 Eoganacht, 40 matched (42 %)

A British Connection?

A review (8/07) of the data from YSearch and SMGF showed the following places of origin for matches to the "South Irish" haplotype:
    YSearch (142): Ireland (63, with Munster names accounting for 51), Scotland (16), England (11), Continent (3), Unknown (49)
    SMGF (83): Ireland (30), Scotland (5), England (7), Continent (8), Unknown (33)

The "Unknown" group includes surnames like White, Brown, Hill, Hunter, Walker, etc., which are vaguely "English", but whether they are genetically Britons, or more recent Anglo-Saxon arrivals from the Continent, is impossible to know. Perhaps someone with knowledge of English and/or Scottish surnames can detect a pattern.
On the other hand, it's possible the non-Irish matches to the cluster are merely the result of statistical convergence, and not indicative of a genetic connection.

A Continental Origin?

Early on, Dr. Nordtvedt identifed several people in the SMGF database carrying the "South Irish" haplotype who trace their ancestry back to north-central Europe. (1 each from France, Belgium, Denmark, and Switzerland, and 4 from Germany.)
Since then, no strong evidence of a connection between the "South Irish" cluster and the Continent has been shown, although the possibility hasn't been ruled out.

An Ancient North/South Divide

In early 2006, Trinity College Dublin published a paper identifying (via STR markers), a group commonly called the "Ui Neill", descendants of Niall of the Nine Hostages, king of Ireland in the early 400's. Later, it was discovered that this cluster was defined by its own R1b haplogroup SNP, M222.
The genetic evidence so far strongly suggests that the "Ui Neill" originated in Ireland (or perhaps Scotland).

It is worth highlighting the fact that this "Northwest Irish" cluster is very different from the "South Irish" cluster. This indicates a different settlement or kinship pattern, between the two halves of Ireland.

The SNP Results

A few people matching the "South Irish" haplotype have been SNP tested. (See the L21 Project results.)

SNPs which are derived (i.e. positive) are these:
M269, P312/S116, and L21 (The furthest downstream on the Y-chromosome tree.)

SNPs which are ancestral (i.e. negative) are these downstream SNPs:
M37, M222, P66


[1] My own very crude analysis of YSearch data (28 entries from 2/06) shows that the "South Irish" haplotype markers have the following elevated percentages over the "Atlantic Modal" haplotype markers at specific values:
    391 = 10 (32% in AMH, 96% in S.Irish, +64%)
    385b = 15 (20% in AMH, 82% in S.Irish, +62%)
    439 = 11 (15% in AMH, 92% in S.Irish, +77%)
    447 = 24 (19% in AMH, 89% in S.Irish, +70%)
    456 = 15 (34% in AMH, 85% in S.Irish, +51%)
    442 = 13 (10% in AMH, 64% in S.Irish, +54%)
    C4 = 24 (a non-FTDNA marker, so unknown)
    390=24 (55% in AMH, 85% in S.Irish, +30%)
    458=17 (50% in AMH, 85% in S.Irish, +35%)
    449=29 (39% in AMH, 71% in S.Irish, +32%)
    H4=11 (67% in AMH, 96% in S.Irish, +29%)
    (the 464 set of markers and the 570 marker also showed elevated percentages, but to a lesser degree)


Atlantic (AMH) R1b haplotype
Northwest Irish (Ui Neill?) R1b haplotype / [short version]
Irish Type 3 (Dal Cais?) R1b haplotype / [short version]
Leinster (Laigin?) R1b haplotype / [short version]
Whelan/Phelan (Deisi Muman?) R1b haplotype / [short version]
South Irish (Eoganacht?) R1b haplotype / [short version]

South Irish - YSearch matches

South Irish - SMGF matches

Update (April 2010)

L21 remains the furthest downstream SNP.
A Grfffin (in the O'DONOGHUE project) was tested as L226-, and a Roddy was tested as L159.2-.
No results have yet been reported for L193, but the STRs for the L193+ people are not similar to the South Irish haplotype.

Originally posted: 2/22/06
Last revised: 4/30/10