Leinster Modal – L159.2 mutation

Our Adams family cluster has tested positive for  L159.2 in three lines. I think it is safe to say all members of family group A033 will test positive for this because our origins are common.

Results: R1b1a2a1a1b4f – L159.2+ haplogroup.

So what does this mean?

The L159.2 mutation is found in descendents of the Ancient Kings of Leinster Ireland specifically Dermot MacMurrough. It means they are cousins of ours dating back 1,500 to 2,000 years (as I understand it anyway – Gerry, please correct me as needed). It is also associated with the R-Z255 mutation.  In 2011, a new SNP – Z255 – was discovered and was ascertained to be upstream of L159.2. The Z255 and Subclades Project I link to below serves as a repository of data for both of the main lineages that inherit the distinctive Irish Sea Haplotype, which is mainly found around the Irish Sea coasts of Great Britain and the province of Leinster.

Our distant ancestors were maritime travelers who populated the Irish Sea coasts and lands as far north as Norway and south past Normandy to Spain. Though, from what I have read thus far, it is unclear if they originated from the Viking North or the Mediterranean. There are theories and speculation that our origin lay with the Damnonii of Ptolemy’s Geographica. There were three main area’s occupied by these peoples –
  1. Domnainn or Fir Domnann of Leinster Ireland
  2. The Dumnonii of Scotland – William Skene, the Scottish antiquarian, also mentioned the Domnonii of Scotland:  “…the great nation of the Domnonii lay north of the Selgovae and Novantae, separated from them by the chain of hills which divides the northern rivers from the waters which flow into the Solway, extending as far north as the Tay. South of the Forth of Clyde they possessed the modern counties of Ayr, Lanark, and Renfrew, and, north of these estuaries, the counties of Dumbaton and Stirling and the districts of Menteith, Stratherne, and Fothreve, or the western half of the peninsula of fife. They thus lay in the centre of Scotland, and were the novae gentes whose territory Agricola ravaged.”
  3. Domnonii of Wales and Cornwall. From, “Celtic Scotland, the Picts, The Scots & the Welsh of Southern Scotland.” by H.M. Chadwick: “In Ptolemy’s map four peoples are located in the south of Scotland. The points of the compass are erroneously stated (cf. p. 72); but it is clear that he means to place the Noouantai in Galloway and perhaps Dumfries, and the Uotadinoi (written Otalinoi?) on the east side, between the Forth and the Tyne. The Selgouai lie between these two peoples, and the Dumnonioi (miswritten Damnioi, Damnonioi) north of the Selgouai, extending apparently from Ayshire into Perthshire. All these peoples are usually assumed to be British. But only one of them survived in later times – the Votadini, known as Guotodin, Gododdin, in early Welsh poetry. The Dumnonioi were presumably of the same stock as their namesakes in Devon and Cornwall (cf. Chapter v above). The latter were certainly British in later times; so it is inferred that the northern Dumnonioi were likewise British. But, as we have seen, another branch of the same stock is found in Ireland – the Domnainn or Fir Domnann of Leinster – and it is apparently nowhere suggested that they spoke any language but Irish

There is some debate if these three peoples were really connected or not. I personally think they were based on what I have read thus far and that we know our Adams who came from Scotland back to Parrish of Cumber, Londonderry, Ulster Ireland around 1660 match the Leinster Modal.


To learn more you can go here:

The goal of this project is to discover the origins of both Z255 and L159.2. There have been some interesting observations:
  1. A number of families associated with the Kings of Leinster and Diarmaid MacMurchada (Dermot MacMurrough) are L159.2+: O’Byrne, Kavanaugh/Cavanaugh, and Kinsella.
  2. L159.2 is mostly found in coastal areas of the Irish Sea, including the Isle of Man and the Hebrides
  3. L159.2 can also be found in Norway, from Troms in the North, to Møre in the South. Whether it arrived there in the Viking Age or earlier has yet to be discovered.



More Notes copied from other locations on the Leinster Modal.

From: Lochlan@aol.com
Subject: [DNA] The 464x ccgg project Results
Date: Wed, 3 Sep 2008 18:55:08 EDT

The 464x ccgg project Results

Regular readers of this list will recall the early excitement caused by the
464x test developed by Thomas Krahn, then of DNA Fingerprint (later bought by
FTDNA), first promoted as a way to check your R1b status without the
necessity of an expensive SNP test. But the test soon revealed a cluster of surnames
with matching DNA, most notably Beattys and Byrnes, both early adopters of
the test. What these samples had in common was matching DNA as well as a ccgg
result on the 464x test, considered an unusual result for R1b, 98% of which
tests cccg. Some DNA experts, most notably John McEwan, thought this was a
definite DNA cluster based on a common ancestor who probably underwent a ReCLOH
event that changed the normal R1b cccg pattern at DYS 464 to ccgg. John
described the cluster as “moderately old”. Others including Thomas Krahn were
more cautious, advising that the ccgg condition was “too volatile” to be used
for genealogical research. One surname included in early ccgg testing
(Eckersley) was later found to be cccg.

The Beattys and Byrnes have a strong DNA pattern characterized by 14-13-30
at DYS 389-1 through DYS 389-2; DYS 448 = 18; and DYS 442 = 11. So far every
Beatty and Byrnes who match this modal (described variously as the Leinster
modal, Irish Sea modal, Beatty-Byrnes modal) have tested ccgg on the 464x test,
with the exception of one Byrnes, who tested cggg, probably the result of a
second ReCLOH event.

We do not know what the connection could be between Beattys and Byrnes. The
Beattys were a mostly lowland Scottish clan the best-known group of whom were
border reivers. The Byrnes of Ireland were chieftains of the Lagin in
Ireland (Leinster). The Lagin chieftains of Ireland also included surnames such as
Kinsella, Kavanagh, Murphy, O’Toole and others. We soon found numerous
Kavanaghs and Murphys who also matched the Leinster modal; samples of each have
tested ccgg. More recently we’ve found several Kinsellas who also match the
Leinster modal; so far none of these have been tested at 464x but they too will
most likely be ccgg.

What we’ve found then in our 464x ccgg project is a common DNA thread shared
by different surnames linked to the ancient Lagin of Ireland: Kavanaghs,
Kinsellas, Murphys, and O’Byrnes. It also appears in a number of other
typically “Leinster” surnames such as Dunphy, Cullen, Tynan, McEvoy and others with
no known clan affiliation. The DNA also appears in Munster but is almost
unknown in the north of Ireland. The McHales in the project are from Co. Mayo in
Connacht. In the Trinity DNA study the Leinster modal DNA is almost as
numerous in Munster as in Leinster, appearing in small amounts in surnames with no
connection to the Lagin of Leinster (a few O’Sullivans, McCarthys and

Perhaps the best known of the Lagin or Leinster chieftains were the
MacMurroughs. Dermot MacMurrough was the king of Leinster who c. 1170 invited the
Normans into Ireland. This line later splintered into the Kavanaghs and
Kinsellas. Despite the encroachment of the Normans on their territories in Leinster
these two families maintained their prominence in the south of Ireland until
the 1600s. The O’Byrnes were also a powerful Leinster sept.

There are other surnames that match the Leinster modal and have tested ccgg.
Many of these appear to be Scottish: McCloughan, McLaughlin, Carmack,
McInvale, Ferguson, McDonald, McConnell, Davidson. In Ireland some of the other
matching surnames are D’Arcy, McHale, Whalen, Quigley, Cullen, Foley, Jordan.
Two of these surnames in Ireland are typically Norman in origin: D’Arcy and

In addition to this large related ccgg cluster we’ve also found others who
test ccgg but are probably not a part of the same cluster. Most don’t match
the Leinster modal closely if at all and most are a large genetic distance from
the ccgg cluster. So far we’ve found six such samples. Nor do any these
really match each other. It appears then that the ReCLOH condition is “volatile”
in the sense that it can happen at any time in any line and those testing ccgg
are not necessarily related to each other. But it also appears to be a
fairly stable condition. We have no idea what the connection is between the
Scottish ccgg in the cluster and the Leinster chieftains but we do know from
historical sources the Lagin were in Leinster well before 400 A.D. and probably
from the time of the Roman conquest of Britain. The odds are good that this DNA
cluster split apart into different branches by at least 400 A.D. if not
earlier and the ccgg condition has remained stable for over 1,500 years,
accompanied by a distinct, easily recognizable modal in STRs.

The surnames in our “unclustered” section who tested ccgg but don’t match
the Leinster modal cluster or each other are McMillan, Kelly, McFarlane,
Hudson, Fletcher, and McSum (Maxham). We have to assume each of these men also had
ancestors that had a ReCLOH event that changed cccg to ccgg but were
unrelated in any way. None of these DNA samples pull up significant numbers of
matches in Ysearch.

So far the only large ccgg cluster we’ve found is the Beatty-Byrne ccgg
cluster (Leinster modal cluster). Searches in Ysearch routinely pull up around
200-300 or more solid matches. So far everyone who has tested ccgg in this
cluster matches at least part of the Leinster modal. There are 32 matching
samples in the project. All have some variation of 14-13-30 (DYS 389-1 through
DYS 389-2). Two are 15 at DYS 389-1. All but 2 have DYS 448 = 18. All but 2
have DYS 442 = 11. The most any of them miss are at two parts of the modal.
All have at least one part of the modal.

Who were the Lagin in Ireland? According to O’Rahilly (Early Irish History
and Mythology) they were Britons from Armorica in Gaul who came to Ireland
fairly late in history (perhaps after 100 BC). In Ireland their tribe names were
the Lagin, Domnain and Galioin, names which O’Rahilly and other historians
have linked to the Domnonii of SW England (Devonshire and Cornwall). Most
historians also see definite connections between the Domnonii of SW England and
Armorica or Little Brittany (now Breton) in France. There was also a tribe
with an identical name in the lowlands of Scotland in Ptolemy’s map (c. 150
A.D.). No one knows if they are related to the southern Domnonii.. The old
territory of the Domnonii in lowland Scotland was centered at Dumbarton and by 400
A.D. was known as the northern British kingdom of Strathclyde. Other
historians have seen links between the Lleyn peninsula in northern Wales and the
Lagin of Ireland.

We do not know for sure who the “Lagin” of Ireland were but it is
interesting to see this relatively rare DNA popping up in surname groups said to be
related in Leinster.

There are several modals on Ysearch that describe the main ccgg cluster.

UKCMV (DYS464x ccgg Project Modal )
AKAZY (McHale Test Values)
VQHHX (464x ccgg Project Modal (FTDNA)
B9NW4 (Byrne Leinster Modal)

You can find the 464x ccgg project at FTDNA at this link:


Or just search FTDNA for “contains” and “ccgg.”

John D. McLaughlin
Member of the 464x ccgg Project at FTDNA

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