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The O'Donoghue Society

For all those interested in history and genealogy and whose names are derived from the Gaelic

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Irish research
Again its the time and effort you put into it, Irish research is a minefield, as with any genealogy research, but more so with Irish , careful planning, recording everything, keeping everything, and most importantlybacking up everything on separate disks, and removable media, and good old paper copies.

yDNA Interpretations


The different links on the Society website provide a history of the Ó Donnchadha name and the various clanns/tribes which identify them. The Y-DNA results are divided most clearly between the Kerry tribes of Eoghanacht O’Donoghues, whose history claims descent from Eoghan Mór and the Milesian warriors of mythical times, and the several tribes of Donohoes of county Cavan, traditionally a branch of the Uí Briúin Bréifne. In addition there are a number of clusters that have possible connections to other Ó Donnchadha clans as well as clusters with current unknown origins.  Following a few general sections concerning recognizing haplotypes, we will discuss the clans/clusters we have identified.


In addition to the STRs that are tested to identify an individual’s haplotype, SNP’s (Single-Nuclear Polymorphisms) are also found on the Y chromosome. Since SNPs play a significant role in differentiating some of the groups, a brief summary of them will be useful before proceeding to the particular clusters.

While both STRs and SNPs can back mutate (return to an ancestral value) SNPs are more stable than STRs and mutate infrequently so that they can clearly identify a subclade. They are used to separate the different haplogroups and their subclades. The International Society of Genetic Genealogists maintains a haplotree at which shows the hierarchy from the root of 'Adam' and includes all subclades downstream of each designation.  It is being regularly updated as more SNPs are discovered through Y-DNA testing and is unlikely to be completely current. Project participants can also see the Haplotree on their own personal pages at Family Tree with the indication of where they are listed in that hierarchy.  If they have not tested for any SNPs, their haplogroup subclade will be predicted by Family Tree.

If a person is ‘ancestral’ for an SNP, this means he does not have a mutation at that position on the chromosome and his ancestors’ Y-DNA never contained that mutation. He is ‘derived’, if his ancestor carried that defining SNP.  While much less frequent, it is possible that a chromosome will back mutate similarly to an STR, as described in the DNA Basics section, and the site of the SNP on the chromosome will revert to its ancestral state.

Family Tree offers a variety of different SNP tests, from testing an individual test, to testing an SNP Pack, which tests a selection of known SNPs within a limited section of the haplotree, to testing the Big Y500, which is an extensive test covering a large part of the Y-chromosome and identifying any mutations found there.  This is where the discoveries are being made. The BIG Y test has become very popular with those interested in further defining their position within their subclade.  A huge number of new SNPs have been discovered through this test in all haplogroups and subclades.  The O'Donoghue of the Glens was the first in the project to avail of the BIG Y, and over 20 O'Donoghues have by now also received their results.

There are haplogroup projects to study the increasing amount of information about the various branches on the haplotree.  Elizabeth administers the R1b-CTS4466 Plus Project, which researches the Irish Type II subclade to which The O’Donoghue of the Glens belongs.  She is also a co-administrator of the R FGC11134 & Subclades project, which is the haplogroup upstream of R1b-CTS4466, and the R DF21 and Subclades project, which studies the haplogroup in which a number of the O’Donoghue Mór-Ross lineage belong.

Irish SNP's

There are four main Irish subclades of the SNP L21, which is the most prevalent haplogroup in Ireland.
The first Irish subclade to be identified was the Northwest Irish Modal Haplotype/Type I, based on its distinctive marker values.  It was discovered within the genetic genealogy community by David Wilson in late 2004 and it was further studied during the Smurfit Institute of Genetics’ project at Trinity College and independently named the Irish Modal Haplotype.  They described the haplotype, predominating in the northwestern areas of Ireland, as being that of the Ui Neill. The TMRCA (Time to Most Recent Common Ancestor) they calculated of 1730 years ago has a standard deviation (SD) of 670 years that could place the common ancestor much later, or earlier, than the 4th century in which Niall of the Nine Hostages was most likely to have lived.  The current thought is that the haplogroup originated about 2000-2200 years ago.  Thus, while it is almost certainly an older subclade than the time of Niall, there was press and publicity about it when Trinity published their paper in the American Journal of Human Genetics in November 2005 which captured the public’s fascination, and the NWIMH/IMH has become synonymous with Niall, even to the extent that Family Tree uses it as a benchmark for those matching the modal.
In February 2006, research identified the SNP labelled M222 as distinguishing this subclade. You can find more information about this Irish subclade at these two websites: and, where you can join the Family Tree R-M222 Haplogroup Project if you belong to this subclade.
The South Irish Type II Haplotype was identified by the respected physicist and citizen scientist Dr. Ken Nordtvedt in 2006.  It too had distinctive marker values, with the majority of males carrying it found in Munster.  Our O’Donoghue of the Glens matched this modal, and he was tested through the Walk-the-Y project in hopes that a defining SNP would be discovered to distinguish this tribe, but on the section of the Y chromosome tested, no unique SNP was discovered.  However, through the Geno 2.0 project at National Geographic,, an SNP was discovered that defined the Irish Type II haplotype - CTS4466.  The BIG Y has since expanded the numbers exponentially, identifying a myriad of different branches within the main subclade of CST4466.  You can read more about them at the R1b-CTS4466 Plus Project - - that Elizabeth and several colleagues launched to study the SNPs defining the Irish Type II haplotype.  It is predominant amongst the surnames associated with the Eóganacht dynasty, but not limited to them.
In late 2009 a new SNP named L226 was discovered via the Walk-the-Y project at Family Tree which was determined to be a defining SNP for the Irish Type III haplotype, which predominates in the west of Ireland.  This is the haplotype of, amongst others, the O’Briens and the other Dál gCais tribes who are descended from the O’Briens in the genealogical tracts.  Though propaganda of the time claimed the Dál gCais descended from a brother of Eoghan Mór, in order to provide them with a royal lineage entitling them to rule Munster in opposition to the Eóganacht, the Dál gCais are considered by historians to have originated amongst the Déisi tribes.  Y-DNA has shown that L226 is not related to what is considered the Eóganacht genetic signature, hence confirming historical opinion.  . There is a website created by Dennis Wright that is devoted to Irish Type III at  It contains a thorough discussion of the findings to date.  The Family Tree R-L226 project is at

There is a Leinster Modal Haplotype identified by the SNP L159.2 with a dedicated project at Family Tree which can be found at  It has also been described as the Irish Sea Modal insofar as it is found with frequency on the English side of the Irish Sea as well as in Ireland.  This mutation is somewhat volatile and the website explains that ‘This SNP is a parallel mutation that exists also within Haplogroup I2a.’ and also ‘The first discovery of L159 was within Haplogroup I-M26; it was then found within R-L21. FTDNA designated them L159.1 and L159.2, respectively.’ There are a number of observations made on the Goals page of the website.  For L159.2 found in Ireland, ‘The majority of Irish samples are from coastal Leinster (Dublin, Wexford, Waterford, Kildare) and Munster (Cork).  
SNP testing in the Mór tribe have identified branches in the DF21 and Z253 haplogroups.  These will be discussed further below.

Palindromes and recLOH

Along the Y chromosome, there are sections which ‘loop’ out from the main strand for the DNA. Multicopy markers are often found on these loops, and the nature of such configuration sometimes creates a cross-over in a way that the allele value of one locus overwrites onto another, resulting in a loss of difference. This results in a ‘recombinational loss of heterozygocity’, or ‘recLOH’. For example, DYS 459a & b, whose modal is generally 9-10, becomes 9-9.  These events can sometimes help identify a commonality between haplotypes and identify relationships (though it is not yet the case for any of the kits in our project).

DYS459 and DYS464 are both on palindromic loops and can tend to mutate at the same time.  Such corresponding mutation events appear to have occurred in the Irish Type III modal.

RecLOH events are considered to be more stable than STR’s but more mutable than SNP’s.

NPE - Non Paternal Event

This is a term used in the genetic genealogy community to indicate that the paper documentation regarding the parentage of the individual does not match what the Y-DNA reveals. This undoubtedly has the potential to create upset, but there is no need to jump to conclusions.
There are various reasons for an unexpected Y-DNA result.  The person could be adopted into a family, or a father/grandfather/etc. could have been adopted.  The mother may have remarried and the husband gave her children his name.  In the case of the Irish, when surnames came into usage, it was usual that the people under the protection of the local chief assume his surname as part of the tribe.  They were not always actually related to him.  It also happened that people would take the name of a powerful individual, just to have the same name, regardless of whether there was any tribal connection or not.
In the case of the Raithlind O’Donoghues, they used the umbrella name of Clan tSealbhaig to encompass all the smaller tribes under their protection.  This way, the people retained the name of their own head of family rather than assume the name O’Donoghue.  That could be a reason for the more modest number of participants found to belong to the Mór tribe.  In addition, a few years after the defeat at Kinsale, Rory O’Donoghue, the last acknowledged O’Donoghue Mór, took a company of men with him to the continent in 1606 and served in Spain, then later France. It’s likely that many of that company were O’Donoghue cousins, whose progeny have been lost to history.  It would be interesting indeed if someday we find a match to the Mór lineage with a Spanish or French name.  Testing in these countries is increasing, so there is such a possibility.

The Eóganacht O’Donoghues of Kerry and Cork

According to Irish myth and legend, all the Eóganacht tribes descend from the second Eoghan Mór, who is purported to have died around 195 - 250 AD, depending on the source.  Almost all the traditional surnames of the different septs of Eóganacht in Munster are dominated by the Irish Type II haplotype and the SNP CTS4466, which could give some credence to the timeline and descendancy from Eoghan Mór, if it were not for the fact that the majority of tribes present in Munster prior to the emergence of the Eóganacht are also dominated by the Irish Type II/CTS4466 haplotype.  This is documented in Elizabeth’s Munster Irish research project -  It is her opinion that though some clans may have a genetic relationship that supports the possibility of them having a common ancestor, the mythology uniting all the leading tribes of Munster into a homogeneous ancestry was politically motivated rather than historically accurate.  Her position is that the Y-DNA evidence negates the likelihood that there was any true common ancestor of the Eóganacht tribes as the annals suggest.
Moving to the second millennium, many histories describe the O’Donoghue Mór and Glens lines as originating from two sons of Awly Mór (d.1158).  He was the champion of Kerry who staved off the attempted conquest of south Kerry by the O’Briens of Thomond, built the cathedral at Aghadoe and solidified the Eóganacht Raithlind presence in Kerry.  The Annals of Inisfallen record a number of sons of Awly Mór.  The two of most interest are Domnall and Conchobhar, from whom the two lines of Glens and Mór are said to have descended.  But where they really brothers?  This assumption seems to stem from one entry in the Annals of Innisfallen in 1178, where it is recorded ‘Conchobur Úa Donchada do marbad’, which translates to ‘Conchobar Úa Donchada was slain’.

In the edition of the Annals edited and translated by Seán Mac Airt, first published by the DUBLIN INSTITUTE FOR ADVANCED STUDIES in 1944, it is noted that the phrase {la Domhnall, lá [a] dearbrathair fein} was interlined by an additional hand, apparently at a different time.  Though the translation is shown as {i.e. by Domnall, his own brother} it may not be that simple.  While we don’t wish to impugn Mac Airt’s scholarly translation, dealing with old Irish can be quite difficult.  It could mean ‘dear friend’.  There are no other contemporary records that suggest this relationship, and this single entry poses several questions.  Who knows when it might have been appended, by whom, or why?  It would seem that all later references of the two sons hinges on this possibly misunderstood term.
Our current Chief of the Name, Geoffrey O’Donoghue of the Glens, belongs to one of the branches of the Irish Type II haplotype, commonly found in the different Eóganacht septs.  Tighe O’Donoghue/Ross (the official historian of the Society) has a very detailed family tradition that his ancestors belong to the line of the O’Donoghue Mór.  Some of this history has been recounted in Tighe’s article ‘The O’Donoghues of Ross’ in the January 2002 Journal.  Tighe’s Y-DNA results differ from that of The Glens, which supports the concept that the two Kerry Eóganacht O’Donoghues did not, in fact, descend from brothers.
The Y-DNA project overturning the assumption of the two lines descending from brothers is not a particular surprise, since historians Canon O’Mahoney and W. F. T. Butler both noted that there were two separate Uí Donnchadha tribes in the first millennium, that of the Eóganacht Cashel and the Eóganacht Raithlind.  A careful search of the annals confirms contemporary O’Donoghues of different lineages in the 11th century.
The research initiated by our first administrator, Prof. Tom Donahue at the outset of the project determined that the Glens tribe is of the Hy Donnomoii, the senior branch of the Eóganacht Cashel, which also includes the McCarthys and O’Sullivans.  According to the annals, their likely progenitors were thought to have separated from the Eóganacht Raithlind around the 5th century when Corc of Cashel was supposed to have established his tribe in Tipperary after his group’s return from several generations in Wales, raiding the Roman settlements there.  However, SNP testing has complicated this assumption even further, since The Glens belongs to one branch of the CTS4466 haplogroup, while the main line of O’Sullivans are in a completely different branch of CTS4466 and are not likely to be related to the Hy Donnomoii within the suggested timeframe of the annals.  In addition, while there are several different branches of McCarthys who are CTS4466, a few relatively close the The Glens, extensive research by Nigel McCarthy through the McCarthy Surname Study has shown that the main line of the McCarthy Mór lineage is actually in a different haplogroup altogether.  Likewise, the Raithlind/Mór lineage is also in a different haplogroup than The Glens, as previously mentioned.
It should be noted that Nigel McCarthy has published a very scholarly paper, AN IRISH TYPE II TIMELINE EXPLORED THROUGH UÍ CHAIRPRI AEBDA, along with a detailed tree of S1121, an early branch of CTS4466, that posits a ‘POSSIBLE S1121 ALIGNMENT WITH SOME EÓGHANACHT GENEALOGIES’ that supports an Eóganacht descent from Oillioll Olum, father of Eoghan Mór II.  While these theories certainly bear due consideration, Nigel’s hypotheses do not altogether align with Elizabeth’s conclusions as stated previously, which are more skeptical of the Eóganacht mythologies.  Nevertheless, both are food for thought.
We will now address the various septs of O’Donoghues as grouped in the project.

The O’Donoghue of the Glens tribe

The Glens ancestor, Dúngal Ua Donnchadha, Petty King of Cashel (+1025) ruled in Tipperary until the mid-century when these Ui Donnchadha finally lost control of the province to the O’Briens.  By the 1100s they were driven from power and out of Tipperary by the McCarthys, and we see little of them in the annals after that until they show themselves in Kerry, first in Glanerought.  The Glens line eventually settled in part of the Mór territory east of Killarney along the glen of the river Flesk. Later histories contain uneven references to the Cashel O’Donoghues and they are sometimes not mentioned at all, but that could be said of other families as well, depending upon the sources used.
The current O’Donoghue of the Glens Y-DNA tested at the outset of the project, and as mentioned, his haplotype matched the Irish Type II modal.  At that time, SNP testing was in its infancy, and it was automatically assume that anyone who also matched that modal was related to The Glens.  As it happens, almost everyone who matched the Irish Type II modal had family origins around Glenflesk.  However, with the advent of increased SNP testing, a number of different branches beneath CTS4466 have been identified, making clear that not all Irish Type II O’Donoghues are directly related to the chiefly line.
This would not necessarily mean that the other Irish Type II O’Donoghues with ancestors from Glenflesk were not part of the tribe.  As explained in the section above, NPE - Non Paternal Event, it is impractical to expect that all members of a tribe were literally related to the chief.  This makes them no less members of the tribe.
The contention that The Glens’ ancestor was a son of Awly Mór is possibly due to the scion heir of Cashel being adopted or fostered by the O’Donoghue Mór Chief.  There was a common practice noted in the Brehon laws that P. W. Joyce explains in his Social History of Ancient Ireland. “An adopted person was called Mac Faosma, literally ‘son of protection.’ Sometimes not only individuals, but smaller tribes, who for any reason had migrated from their original home, were adopted; who were then known as finé-taccuir, i.e. ‘a family taken under protection’.” This could explain the common notion that the Mór and Glens lines were from sons of Awly Mór. There is no other adequate explanation for why Awly Mór’s territories were divided after his death, rather than his táiniste/son being given rule of the whole territory, which would have been the normal method of succession.  The two lineages retained close ties of kinship throughout subsequent history.
With the multitude of SNP testing over the last few years, we have identified a number of branches related directly to The Glens lineage.  Our first group in the Results spreadsheet on the Family Tree website - - is that of The Glens himself and a distant cousin with a pedigree going back to the 17th century when his Duff line descended from a brother of the chief of the time - A. Eoghanacht Cashel/The Glens - CTS4466 - A802 > A914 > BY121634+ - The Chief of the Name & the descendant of the 17th century Duff line.
The second group is A1. Eoghanacht Cashel/The Glens - CTS4466 - tested or likely A802 > A914+ - The Chiefly line.  This group, by their haplotype match and/or SNP testing, likely descend from the family of The Glens at some point since that Glens genetic signature mutated to a 13 at DYS485.
The small A2. Eoghanacht Cashel/The Glens - CTS4466 - A802+ > A914- group would be related to The Glens line prior to the mutation just mentioned.
The A3. Eoghanacht Cashel/The Glens - CTS4466 - other branches group contains the other Irish Type II haplotype O’Donoghues who are in a different branch of the Irish Type II tree, nevertheless united by their origins in Kerry or Cork.
Since the Ó Donnchadha of Ossory are historically supposed to have been an offshoot of the Cashel Eóganacht, I placed the two Dunphys in the A4. Uí Dhonnchadha of Ossory? (branch of Cashel) - CTS4466 group due to their haplotype and family origins.  I included the '?' partly because there are only two of them, but they are distantly related and fit the location and historical origins of which we are aware.
The group includes four individuals of the Glens tribe still living in their ancestral territories in addition to The O’Donoghue of the Glens, who now lives in Offaly.  Though not tested A914 yet, all four men are likely to be of the chiefly line.  The most significant division within the group is of seven individuals with slightly different alleles at two of the multi-copy markers – DYS 385b, DYS 464d, DYS CDYb and DYS 442, four of which can trace their families back to a common ancestor in the US, though not across the water.
There are also four participants whose birth name is O’Donoghue.  For one, his results exactly match another Glens member, and they have communicated to discover a common ancestor, which has opened up a whole new family history to enjoy.  This is a wonderful success story.
There is also a McCarty who matches O'Donoghues far closer than other McCarthys.  It's quite likely that his heritage is the McDonogh McCarthys from centuries back who Rod has always suspected were O’Donoghues.

The O’Donoghue Mór tribe

The O’Donoghue Mór tribe belongs to the Eóganacht Raithlind, which also includes the O’Mahoneys.  This tribe of Eóganacht is considered by many to be the senior branch, with the other tribes separating from them and establishing their own identities at various times through the centuries.
Within the Mór tribe, there are several subgroups of individuals.  The Results Spreadsheet separates those smaller subgroups.  Initially, it was presumed that they were all related at some point in the historical past of the Eóganacht Raithlind.  However, with all the additional SNPs that have been discovered and tested, it has become apparent that while these separate groups have a historical connection to the tribe, they do not all share a genetic relatedness as had been anticipated.
Tighe O’Donoghue/Ross is in the B. Eoghanacht Raithlind/Mór-Ross - DF25 > DF5 > BY14464 - The Chiefly line group along with his ‘cousins’.  His family tradition of descending from the Mór/Ross lineage was instrumental in recognizing that there is indeed a separate lineage of that lost dynasty from the 1583 death of Rory O’Donoghue Mór and the later attainder in 1586 of the last documented O’Donoghue Mór of Loch Lein, his son, also named Rory.  According to family tradition, the Mór family moved to the Glens lands after the attainder and remained there till the Rightboy movement of the Tithe wars, when the then O’Donoghue of Ross became Captain Right, the leader of the movement (see ‘Captain Right – The Rightboy Movement and the Tithe Wars’ in the Jan 2004 Journal).  Eventually caught and banished to the Burren of Clare, Tighe’s grandfather was one of those descendants who emigrated to the US from that county in 1905.  Since his testing, three more individuals have tested and found to match Tighe, two of them aware of their Clare roots, though their family’s’ illustrious/infamous history was lost in the mists of time and the tribulations of staying alive on that barren landscape until the present day.
Kit B9394 tested the Big Y-500, and both Tighe and kit 600366 ordered the R1b-FGC5780 SNP Pack, which included a number of B9394’s ‘private’ SNPs.  They both matched all kit B9394’s SNPs (except one that didn’t provide a result [a dud...]) confirming their close familial relationship.  We unfortunately have not discovered any O’Donoghues around Killarney that are remnants of that family before they were banished to the Burren.  There is one gentleman with only 12 markers tested, with whom we have lost touch, so we are unable to discover more about him and him family origins, though the given names suggests he may be one of this group.
Group B1. Eoghanacht Raithlind/Mór-Ross - DF25 > S6185 > BY39558 are distant cousins to the chiefly line, insofar as they split in their genetic history with them at DF25 and travelled down a different branch of the tree.  This group includes our founding Group Administrator, Prof. Tom Donahue, whose family tree leads him directly to Coomacullen Mountain about three miles from Glenflesk.  While he originally supposed that his geographic location placed him within the O’Donoghue of the Glens tribe, his haplotype indicated otherwise.  Another match, 25488, has origins in Tipperary prior to emigration to the US, but his research indicates that there does seem to be a Kerry connection as well.  Another recent participant, 190709, who is a genetic distance of one at 37 markers from 25488 has been able to find a common ancestor back in the 18th century.  More recently, an adopted gentleman, N61117, has also discovered that he is related to both 25488 and 190709, giving us more success stories in finding cousins.
Kits 358147 and 643196 have tested the Big Y-500, and a surname-specific branch for them was identified – BY39558.   It is likely that all the gentlemen in this group are positive for BY39558.
There are 15 gentlemen in Group B2. Eoghanacht Raithlind/Mór-Ross C - Z253, including our Society founder Rod O’Donoghue, who hail from Kerry to Limerick, which would have been the northernmost reaches of the original Mór territories.  They all have rather close connections, with two matching exactly at 37 markers who have found their common ancestor in a family of four brothers of the early 1800’s.  Another member, a genetic distance of two (from the two just mentioned) at fast mutating markers, has a family tree connecting him to one of the other four brothers. The remaining participants of this group have in all likelihood a connection near the time of the four brothers – perhaps a generation or two further back.  They are still searching records to see if they can find the common ancestor.  Rod has found his origins in Ireland (see ‘Serendipity or what!’ in the January 2012 Journal, ‘The O’Donoghues of Ballyduff, North Kerry and its environs’ in the April 2012 Journal and most recently ‘How did the O’Donoghue name get to North Kerry?’ in the July 2014 Journal).
Kit B99579 has tested the Big Y-500, and his terminal SNP is A503 beneath Z253.  Rod is tested to A494, which is upstream of A503.  He too, as well as the others in this group, are likely to be A503 as well if tested.
There are two kits in the B3. Eoghanacht Raithlind/Mór-Ross - other branches group whose origins suggest a Cork/Kerry connection, though they do not match the other B members.
As with the several separate groups in The Glens as well as the Mór, this does not mean that these clusters were not related at all.  From the same territory and under the protection of the chief, by the nature of things, there would have been continual intermarriage between these tribal members as a matter of course.  Families tended to stay within the tribal territories into which they were born. They received protection from the chief of the territory, something which they would lose if they moved or travelled into a different territory.  That was the way of it in those tribal days.  The similarities in physical characteristics in Kerry/Cork O’Donoghues, the similarities in geographic origins of their families and ancestors, some within 25 miles or so from each other, all tell us they are related at some level, through maternal lines or other.

Uí Dhonnchadha of Ossory

Since the Ó Donnchadha of Ossory are historically supposed to have been an offshoot of the Cashel Eóganacht, we placed these two Dunphys in the A4. Uí Dhonnchadha of Ossory? (branch of Cashel) - CTS4466 group due to their haplotype and family origins.  We included the '?' partly because there are only two of them, but they are from Laois and fit the location and historical origins of which we are aware.
We had at first considered that their ancestors were remnants of the Cashel O’Donoghues who remained in the midlands near Cashel, opposed to those who entered Kerry in the 12th century. However, reading through the text of the Historical Origins section of the Society website, it dawned on us that there could be another explanation.
As pointed out in the discussion of the tribe of Uí Dhonnchadha of Ossory, ‘the O’Donoghues of Ossory were a branch of those of Cashel, whose territory was given to the kings of Cashel by the people of Leinster as recompense for the death of their king, after he was slain unlawfully at the Hill of Allen in Kildare by a king of Leinster.’  The territory of the Uí Dhonnchadha is recorded as being Magh Mail, which is in Kilkenny, just south of Laois, where the two Dunphys families originated.  Hence, it is just as likely, if not more so, that the two Dunphys descend from those remnants of the Uí Dhonnchadha of Ossory.  This would seem fitting, since it is said that the name Dunphy arose in the Osraighe territory, though previously none of the Dunphys in the project appeared to support that contention.  Their relationship to the other Glens participants is a bit more distant, also supporting a distant separation in their lineages.

Cavan Donohues

There are four different subgroups of Donohue/Donohoes in the Project. They cross over with groups in the Breifne Clans project.  Joe Donohoe had begun that project and led the research of those various tribes.  We have his major 11 part report of 2009, completed shortly before his passing, available amongst the Y-DNA Reports.  Since then, other administrators have rearranged the Results spreadsheet, and unfortunately little has been done to advance Joe’s work, which would be a tall order in any case.
The C. Cavan Group A - M222 modal matches that of the NWIMH, the Northwest Irish Modal Haplotype.  The origins of this haplogroup was discussed in the Irish SNPs section above.  While the NWIMH definitely has a geographic distribution across the northern counties and over the channel into the Scottish highlands, it’s unlikely its origins can be attributed to any specific tribe.  Joe discusses this subclade in his BCP Report 5 Part 1 and Part 2.
The C. Cavan Group B - L513 belongs to the L513 haplogroup.  Kit 262020 has tested the Big Y-500 and his terminal SNP is BY2940.  It is likely that all those in this group would test positive for this SNP.  This group is discussed in Joe’s BCP Report5 Part 4.
The C. Cavan Group C - L513 is likely to belong to a different branch of L513, though no one in the group has yet SNP tested to confirm.  They have more matches in what Joe described as the ‘FD2MaguireGroup’.  According to his research, the Donohoes of this group (originally MacDonaghy) are a 15th century branch of the McGuires, descending from a Donnchadh Maguire.  Group C is discussed in his BCP Report 5 Part 8.
The C. Cavan Group D - U152 group are in theL20 branch of the U152 haplogroup.  Kit 96227 from the Clan Donnachaidh project joined ours since his haplotype matches these men rather closely, and his TMRCA is also closest to theirs.  He is tested L20, and a second kit is also tested L20, which supports the probability of the whole cluster being L20.  This group is discussed in Joe’s BCP Report5 Part 6.
There is also a C. Cavan Group E.  Two individuals of other surnames have joined the project who match more closely to Donohues than their own surname.  Though there has been no SNP testing, it’s possible they are also a branch of L513.

Uí Dhonnchadha of the Déisi Mhumhan

The largest of our other clusters - E. Uí Dhonnchadha of the Déisi Mhumhan? - L226 - is defined by the SNP L226 mentioned earlier.  The Deisi, considered an Erainn tribe, were the tribe of the O’Briens prior to the prominence of Brian Boru and their claim of being descended from Cas, a supposed brother to Eoghan Mór.
Since this L226 cluster matches the Déisi of the O’Briens, it’s possible that this group is of the Uí Dhonnchadha of the Déisi Mhumhan, so we have labeled this cluster ‘Uí Dhonnchadha of the Déisi Mhumhan?’, using the ? to indicate we are not assured in this designation at this point.  However, the territory of the Uí Dhonnchadha of the Déisi Mhumhan was in Waterford/Tipperary, and most of these O’Donoghues’ families originate in either Offaly or Tipperary.
A Dunphy in the project is also Irish Type III, though his origins are atypical of the others, in Cork back to the early 1800’s. (There is an article about his family in the April 2009 Journal.)

The Osraighe and the Teallach Modharain

There are two occasions when an Eóganacht tribe was overlord of the Erainn Osraighe tribes, the lands of which the Historical Origins link describes as comprising County Kilkenny and certain parts of counties Tipperary and Laois.
The Eóganacht held sovereignty over the Osraighe territories in the 6th century, prior to the local tribes wresting back power and ruling the territories themselves.  However, due to an unlawful killing of the Cashel King by the King of Leinster in the mid 700’s in a battle at the Hill of Allen, an eric (fine) was imposed, and part of the Osraighe territory from Gowran in Kilkenny to Dungrianan in Tipperary was given to the neighbouring Eóganacht Cashel.  O’Hart indicates it remained under their control until the end of the 12th century when Normans seized it.  It is our belief that this group were the Ó Donnchadha of Ossory, as described earlier.
In addition to the Eóganacht sovereignty, there is also record of an O'Donnchadha tribe being kings of Osraighe along with the O'Carroll’s and MacGillipatrick’s.  While there is record of Donal Mac Firbis saying that these O’Donoghues were of Eóganacht origins, it is also possible that they were Erainn.  In the April 2009 Journal, Eoin Ó Donnchadha, kit 97145 wrote a brief article as an introduction to the Ua Donnchadha sept of Osraighe.  His own origins go back to north Wexford, which is not far from the traditional Osraighe territory.  He and a Dunphy, kit 104452 (Dunphy origins are said to be in Osraighe, though more on that below) share an unusual allele value, and Eoin’s own research uncovered that a number of Carroll’s matched his and kit 104452’s uncommon null value at DYS425.  Initially, that supported a connection between the Ósraighe Ua Donnchadha and the O’Carrolls of Ely, whose territory is in Osraighe.
However, Joe Donohoe’s 2009 annual report for the Breifne Clans project contains a well researched, thorough discussion of Oriel surnames and the Airghialla clans of the Oriel territories, including parts of counties Armagh, Monaghan and Louth, abutting Cavan.  There are a number of these Oriel families who contain members with null 425s, and there are a tribe of Oriel Carrolls in this territory.  Hence the Carrolls who are null 425 are probably Oriel O’Carrolls.
There is a new Family Tree project devoted to the Ely Carrolls and corresponding with the administrator, the pedigree of one of the cluster of Carrolls considered Ely supports that the cluster is indeed Ely, and their ancestral haplotype does not match that of our two participants. This makes it unlikely that there is an Osraighe connection for our two null 425 participants.
There has been much research done by many parties since the early days mentioned previously.  A Clan Colla null 425 project was initiated, which is subtitled ‘R-Z3000: DNA of "The Three Collas" - rulers of the Kingdom of Airgíalla’, identifying the major branch under DF21, Z3000 as being peopled almost exclusively by traditional Clan Colla surnames.  See

By now, both kit 97145 and 104452 have tested the Big Y-500.  They have been found to have terminal SNPs of BY24138 (a branch of Z3000) and Z3000.  Based on their SNP results, we have labelled them the E. Airghialla 1 - null DYS425, since they match this modal (also initially labelled by Joe Donohoe).
There was a time when we thought that the origins of these two kits may have been with the Teallach Modharain Ó Donnchadha.  Eóin has researched this tribe, of which, as indicated in Rod’s book, little is known.  Their territory appears to abut Airghialla tribes, but so far no sources have been found which include them in the Airghialla.  Joe Donohoe pointed out in his BCP Report 5, Part 7 that there were no obvious associations between the Dunphy/Ó Donnchadha names and the Airghialla.  Yet, the Big Y results, make clear they must part of that group in some way, geographically/territorially/genetically.  For now, we are using the Airghialla 1 - null DYS425 designation but hope that additional research may clarify this further.

Other Clusters

Elizabeth has labelled the smaller unidentified clusters (insofar as we are not currently aware of a known tribe of O’Donoghues to which they are likely to belong) as Group I through V.
F. Clusters - Group I:  I re-evaluated my designation of the previous Ninussa? cluster and concluded that it was not as defensible as ELIZABETH had felt early on when I first assigned it to Robert Schmoldt (his father was adopted and he does not know his place of origin, though records indicate a Donahue birth name) and Dwaine O’Donohue, based mainly on Dwaine’s origins to be Clare (though it was possibly Cork as well). When Paul Dunfee Johnson joined, since his origins are Wexford, I did not consider him as a match and placed him in the Unaffiliated R1b1 group. When John Donahue joined, with origins in Kerry, I added him to the group since he is the closest match to Dwaine, though puzzled by the Clare/Kerry issue. Taking another look, Paul is truly close enough to be considered part of the cluster, so I have moved him to the group. This does make it difficult to consider the cluster to be representative of the Eóganacht Ninussa, hence I have changed the designation of their group to Group I of the unidentified clusters (since they were identified before the other clusters listed) and moved the other five groups to Group II, etc. Dwaine has tested positive for the SNP of L513, and the rest in that cluster would probably be positive also if they tested.
F. Clusters - Group II - Z253:  Kit 169762 joined the project and his haplotype was rather close to the C. Cavan Group D - U152 mentioned above.  He ordered a Deep Clade test, and Elizabeth expected he would probably be U152 as well. She was wrong!  He is also L21+, as are most of the other tribes who have similarly tested.  This is an example of how ‘convergence’ can occur across Hg R1b, which is so huge as to have unrelated haplotypes appear on the surface to be connected more closely than they actually are. We’ve placed kit 169762 in Group II of the Clusters, with another more recent member who matches as well.

F. Clusters - Group III - U106 > BY50623:  In this group of closely matching individuals, one has tested the Big Y-500 and found to be a branch in the U106 haplogroup – BY50623.  This haplogroup is separate from the most frequent haplogroup found in Ireland of L21.  There is a haplogroup project devoted to U106 at where more can be found about the origins of this haplogroup. 
The F. Clusters - Group IV - Z16943 participants are known relations, uncles/nephews with a known common ancestor in 1776.
Three members of F. Clusters - Group V - L159.2 match the Leinster modal haplotype (though one with only 12 markers).  Two participants have tested positive for L159, the defining SNP for that cluster. One has origins in Wexford, which is within the overall territory of this modal, and an untested kit comes from Kilkenny, not terribly far from the main areas of the Leinster modal.  However, one member tested positive for L159 but was found to be negative for the upstream branch, Z255, which is a bit of an anomaly, along with his origins in the NI/UK.  The possibility of a Big Y-500 may help resolve the apparent disconnect.  It is possible that his is just a third iteration of the mutation.
F. Clusters - Group VI - I-M26 comprises two participants who are haplogroup I2a.  One is a gentleman recruited to the project who currently lives in Glenflesk.  He matches, perhaps within a genealogical timeframe, an individual who has roots in Cork, with a paper trail to the late 1800’s. Prior to their testing, they would both have been candidates for the Glens tribe.  There could be a number of explanations for why they are not.  While not genetically an O’Donoghue on the male line, it is possible that there was intermarriage with female O’Donoghue lines in the distant past prior to the taking of surnames, and being in the tribe, would have adopted the Ó Donnchu when surnames were taken.  As it happens, the Cork member has an exact match with a Haley in the Family Tree database.  Haley is a west Cork name.  And coincidentally, there is a different Haley in our project who matches our Glens tribe, also from Cork.  Elizabeth thinks it can be inferred from this that a related group of haplogroup I2a individuals were living in west Cork and affiliated with the Glens Eóganacht.  When surnames were taken, they split in some way, resulting in some taking the name Haley and others assuming the tribal name of Ó Donnchu.  Their loyalty and heritage would be with the O’Donoghue tribe, even if their genetic heritage was different.
We have a second group of two who are in a different branch of haplogroup I - F. Clusters - Group VII - I-P37.
We have a group of as of yet unaffiliated participants who do not match any of the clusters we have identified - G. Unaffiliated R1b1a2.  While they have the name O’Donoghue, of various spellings, we have not yet found any surname matches, and their genetic heritage is different from the majority of members in identified tribes.  There could be various reasons for these differences, such as suggested previously.  We await more participants in hopes that matches will be discovered.
We have several members who belong to haplogroup R1a in H. Haplogroup R1a1 and further hg I - I. Haplogroup I - but none match each other at this point.  We are hopeful that future members will help us discover more.

There are a number of members in the project who are related to the surname O’Donoghue through the female line.  Some of the gentlemen are also Y-DNA tested, but we do not display their results in the spreadsheet to avoid confusion.


Overall, we have a growing number of Dunphy’s in the project, but interestingly, their haplotypes indicate that there was no single origin of the Dunphy name, even though it has traditionally been considered a chosen change by O’Donoghues in the Osraighe area.

There has been a major update to this page, and we recommend you browse through as your interest takes you.  In future, as new information is added to the link, it will be noted in blue to identify it as new material.  If there is any aspect of the information which you would like to see expanded or addressed, please let Elizabeth know.

Last updated July 2018