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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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Migration - Ireland to England & Wales
There are no records of movement across the Irish Sea. It was a short journey within the same jurisdiction and there was always free movement. We often talk about Irish 'immigrants' but they were just migrants. The only formality was buying your ticket.

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 yDNA results are divided most clearly between the Kerry tribes of Eoghanacht O’Donoghues, who trace their 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.

The Atlantic Modal Haplotype (AMH) and L21

A modal haplotype is a compilation and average of the most common allele values at each marker for the group which is being defined. Along the western coast of Europe, there is a common haplotype amidst the R1b1 population which has been labeled the Atlantic Modal Haplotype – the AMH.  Several ago, an SNP named L21 was identified. It is a major subclade that appears to be related (though not exclusively) to Celtic territories on the continent, and a large majority of the Irish and British have tested to be positive. The L21 modal mirrors that of the AMH. Those values are listed on line 8 of Spreadsheet A for comparison with the various tribes and clusters.


In addition to the STR’s that are tested to identify an individual’s haplotype, SNP’s (Single-Nuclear Polymorphisms) are also found on the Y chromosome. Since SNP's 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 STR's and SNP's can back mutate (return to an ancestral value) SNP's are more stable than STR’s and mutate infrequently so that they can clearly identify a subclade. They are used to separate the different haplogroups and their subclades. SNP's are listed in a Haplotree table at Family Tree - - which shows the hierarchy from the root of  'Adam' and includes all subclades downstream of each designation.  The drop-down box at the top will give you the draft tree which includes all the newer SNP's being considered for inclusion on the official tree.  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 no longer offers a ‘Deep Clade’ test as such, but they offered a 'Walk the Y' test and then a Geno 2.0 test through National Geographic which offered much greater coverage of known SNPs.   The Geno 2.0 was then overshadowed by other even more advanced tests for an increasingly long list of newly discovered SNPs.  These range from the BIG Y offered by Family Tree to a Full Genome sequence available at  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 five other Glens O'Donoghues have by now also received their results.  These will be discussed further in The O'Donoghue of the Glens section below.

As a result of all these newly discovered SNPs, the naming of the sublclades began to become unwieldy with so many more branches, so Family Tree has changed their haplogroup nomenclature to reflect the furthest downstream  SNP.  Hence for instance, R1b1a2a1a1b3c1 becomes R-U152.

Irish SNP's

The first Irish subclade to be recognized was the Northwest Irish Modal Haplotype, based on its distinctive haplotype. In February 2006, research identified the SNP labeled M222 as distinguishing this subclade.  A number of the Cavan Group A participants have tested positive (derived) for M222, which was expected, since their haplotype so closely matches the modal for that subclade.

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. This defines our possible Uí Dhonnchadha of the Déisi Mhumhan group. 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.  This is the haplotype of, amongst others, the O’Briens and the other Dalcassian tribes who are descended from the O’Briens in the genealogical tracts

There is a Leinster modal haplotype identified by the SNP L159.2 with a dedicated project at Family Tree which can be found at 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).  Group V on our third tab of Spreadsheet B matches this modal.  A newer SNP - Z255 - has recently been discovered that is upstream from L159.2.

One of the members of Group V, kit 174583, had previously tested positive for L159 but surprisingly did not share any of the distinguishing off-modal marker values of the Leinster modal.  He tested for Z255, expecting to be positive for this upstream SNP, but he is, in fact, ancestral - negative for Z255.  There was a discussion of this anomalous situation on the R-L21 Yahoo Forum and  Family Tree was contacted for confirmation that the SNP of kit 174583 was a third iteration of the L159 mutation and could be considered L159.3.  To date, there is only one other individual at Family Tree that has tested L159+ but Z255-.  He is not an O'Donoghue, so either his was a fourth mutation or it occurred quite some time before surnames were adopted.  For the present, kit 174583 remains attached to Group V for comparison purposes.

A Donnachie who joined our project belongs to a subclade identified by a different SNP – U152 – which is quite distinct from the more numerous L21 in Ireland. This gentleman is from Derry, and he matches a group of men in our Project, one of which knows his origins to be Cavan and another who has also tested positive for U152.

Our O’Donoghue of the Glens was tested through the Walk-the-Y project in hopes that a defining SNP would be discovered for the South Irish/Type II haplotype which distinguishes 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,, new SNPs were discovered that define the Irish Type II/Glens haplotype - CTS4466 being the primary one, plus a few others.  The BIG Y has since expanded the numbers exponentially. You can read more about them at the R1b-CTS4466 Plus Project that I and several colleagues launched to study the SNPs defining the Irish Type II haplotype of the Glens tribe.  The project can be seen at

Individual tests for a number of the new SNPs is now available, so if anyone is interested in pursuing a bit of SNP testing, let Elizabeth know and she can research and make suggestions.

The SNP discoveries in the Mór tribe are DF25, DF5/BY3384 and Z253/BY60. These will be discussed next.

The O’Donoghue Mór tribe

The O’Donoghue Mór tribe belongs to the Eoghanacht Raithlind, which also includes the O’Mahony’s. This tribe of Eoghanacht is considered by many to be the senior branch of the Eoghanacht, with the other tribes separating from them and establishing their own identities at various times through the centuries. Eoghan Mór, their progenitor (if he did indeed exist), possibly lived around the time of Christ, give or take a century or so.

Within the Mór tribe, there are several subgroups of individuals.  Spreadsheet A separates those smaller subgroups.  Initially, it was presumed that they were all related at some point in the historical past of the Eoghanacht 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.

The first Group A of nine men include 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, Jerry Donehoo 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, Tim Donahoo, who is a genetic distance of one from Jerry has been able to find a common ancestor back in the 18th century. This is a real success story.  More recently, an adopted gentleman, Merle Thornton, has also discovered that he is related to both Jerry and Tim, giving us another success story.

Tim and Merle have both been tested for the SNP DF21 and found to be positive. Merle also tested positive for DF25, which is downstream of DF21 in the hierarchy of the haplogroup tree. It is likely that all the gentlemen in Group A are positive for DF21 and DF25.

Tighe O’Donoghue/Ross (the official historian of the Society) is in Group B. 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. Tighe’s closest relative in the project is also from Clare, though his 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.

Tighe has SNP tested and found positive for not only DF21 but DF5 and BY3384.  By default, he is also positive for DF25 (tested in Prof Tom's group) since it lies between DF21 and DF5.  Because he is positive for an SNP downstream of Group A's DF25, their relationship could not be a close as comparing their haplotype STR values would suggest.  Cousin Tim has just ordered the BIG Y test, which will confirm that he is also BY3384+.  It will give us more SNPs that may apply to this Group A as well.

There are ten other members on Group C 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, including the founder of The O’Donoghue Society, our own Rod O’Donoghue, 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).

Despite Group B and C sharing the unusual value of 12 at DYS392, which supported our initial assumption that the two groups were related within a historical time-frame, it is now clear that they do not belong to the same subclade.  Rod has recently tested positive for Z253, which is a brother SNP to DF21, as well as a further downstream SNP, BY60.  (Interestingly, the SNP L226 which defines the Irish Type III haplotype is downstream of Z253.  There is a possibility that there may be some kind of connection there, but it would be in the distant past.)

As explained in the October 2013 quarterly report, in actual fact, belonging to different subclades by definition means that a common ancestor must be further back than the STR comparisons suggest.  While Prof Tom’s cluster is DF21+/DF25+, Tighe’s being in a further downstream subclade with DF5+ indicates that it’s unlikely there could have been a familial connection within the roughly thousand years plus suggested in the TMRCA spreadsheet previously displayed in Sheet B on the Society website on the Results page.  This does not preclude that there is a tribal connection, since as mentioned above, the Eoghanacht Raithlind ultimate beginnings date back long before the time of Awly Mór O’Donoghue to the earliest days of the Eoghanacht, if not before the mythical time of Eoghan Mór, the purported progenitor of all the Eoghanacht tribes.

The relationships between Prof. Tom’s, Tighe’s and Rod’s groups are uncertain based only on comparing the STR haplotypes.  At this point in time, the research currently underway for all these different subclades can only provide tenuous possible dates for common ancestors, if any suggestions are made at all.

This does not mean that these clusters were not related at all.  These tribal affiliations could have originated with the appearance of the Eastern Gaels who most certainly did arrive on the island at some point in the past.  They could not conceivably all have been related family members at that time.  There could have been a number of independent groups of cousins loyal to their leader.  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 traveled 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.

There are six additional members in the Mór tribe.  Two match each other exactly at 25 markers, sharing one off-modal allele at DYS 447, and a participant upgraded from 12 to 67 markers to find he is closest to this Mór subgroup. None of them are sure from whence their families came in Ireland, but one of them felt the call of home when he visited Ireland and drove within sight of the Kerry mountains.  Three other participants are not quite as close in genetic distance but retain similarities of haplotype.  Two of them have definite Kerry origins, so we are including them in the overall Mór lineage.

Things are somewhat less complicated for the Glens tribe.

The O’Donoghue of the Glens tribe

Many histories describe the Mór and Glens lines as originating from two sons of Awly Mór (d.1158), 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 Eoghanacht Raithlind presence in Kerry. The yDNA project has overturned that assumption, by clearly separating the lineage of The O’Donoghue of the Glens from that of the Mór. A few historians have posited different origins of the two tribes, and the research initiated by Prof. Tom Donahue has indicated that the Glens tribe is of the Hy Donnomoii, the senior branch of the Eoghanacht Cashel, which also includes the McCarthys and O’Sullivans. Their likely progenitors separated from the Eoghanacht Raithlind around the 5th century, when the annals indicate Corc of Cashel established his tribe in Tipperary after his group’s return from several generations in Wales, raiding the Roman settlements there.

By the middle of the 11th century, the Eoghanacht Cashel O’Donoghues 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 in the mid 1100’s. 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.

As mentioned earlier, this tribe has a number of loci with off-modal values from the AMH. This ancestral modal matches that of the ‘South Irish’ haplotype, also described as ‘Irish Type II’. Surname projects of McCarthys, O’Sullivans, McGillicuddys, O’Mahonys, O'Keeffes and other Eóganacht families contain individuals who also closely match this ancestral haplotype, though there are often other markers with different modal values as well that distinguishes them from other families. This similarity also supports the contention that the Glens O’Donoghues are part of the tribe of Eóganacht Cashel. It also suggests a different origin than the eastern Gaels which the O’Donoghue Mór lineage may embody.

On one level, the Glens tribe is a very coherent group. Strictly based on TMRCA of the STR haplotypes, on average, they are related within 1000 years or less, which coincides with the time frame of the earliest indications of the Glens tribe as a separate entity in Kerry, shortly after the death of Awly Mór. This would seem to indicate that the whole tribe descended from one man, or at most a few closely related individuals who were at that time probably part of Awly Mór’s family, either through fosterage or adoption. 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 how Awly Mór’s territories were divided after his death and the two lineages would have retained close ties of kinship throughout subsequent history. However, the results from the BIG Y test for The Glens and two other Glens members has necessitated a re-evaluation of the relationships, with the realization that not all the Glens members are as closely related as the STR TMRCAs would have suggested.

There is more detail available on the R1b-CTS4466 Plus Project mentioned above, and the January quarterly report discusses the findings. A number of SNPs were discovered amongst the three Glens members tested. All three share the SNP named A804, along with nine other newly identified equivalent SNPs (meaning that anyone positive for one is positive for all of them). These are also shared with a gentleman named Kane, whose family come most recently from Clare.  This was a bit of a surprise, and further research may help us determine the ancestry of this relationship.  His genetic distance with kit 43423/Donahue, who is also A804+, would not necessarily suggest a recent common ancestor.   However, in addition, The Glens and kit 32032 also share ten other additional equivalent SNPs, headed by A802, which are unique to them only.

Reviewing the haplotype values for The Glens and the rest of the group, there is a particular STR value of 13 at DYS485 that was unique to him and a number of other Glens members. Kit 32032 matches that 13 at DYS485, and his BIG Y results match those of The Glens exactly. The other kit, 43423, matches some but not all of the SNPs uniting 32032 and The Glens. This points to a branching of The Glens direct line from the others of the Glens tribe, perhaps some centuries ago. Estimating dates is something I generally prefer to avoid, since there are just so many factors that could affect the accuracy of such predictions. However, it is conceivable that this branching may have occurred back as far as the time frame when The Glens tribe left the Cashel area and settle in Kerry. The fact that 43423's last known antecedents were from Cork rather than Kerry may or may not be of significance.

There is another marker value of 13 at DYS444 that also hints of a close connection to The Glens. There are five members who share that value, though they do not presently have 111 markers tested to see if they match the 13 at DYS485. I've repositioned them in the Society spreadsheet below the clusters that do have the DYS485 match. One of them has ordered the BIG Y during the Family Tree winter sale, as well as another member not as closely aligned, so these results will provide a deeper understanding of the tribe as a whole when they arrive.
The group includes five individuals of recognized branches of the Glens tribe still living in their ancestral territories in addition to The O’Donoghue of the Glens, who now lives in Offaly. 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.

A participant from the Duff cadet line of the Glens has tested to support that he is indeed related to The Glens as his family history indicates.  His results confirm this.

There are two others who have personal haplotypes with a few more than usual off-modal values, nonetheless, we are comfortable with the correctness of their attribution.

There are also three 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 another success story.

There are seven participants of other surnames who match the Glens/Southern Irish modal. One does not know where his family originated, three are from Cork/Kerry and one, though his immediate family originated in Clare, a tribe of his surname is found in Munster, which could explain his matching the Glens modal. There is an O’Neill from Tipperary who matches the South Irish, much the same as four other O’Neills in the O’Neill project who are also South Irish. The genealogical tracts include the name O’Neill as a sept of the Eóganacht Raithlind. While we consider the Glens tribe to be Eóganacht Cashel rather than Raithlind, there is an indication that these South Irish O’Neills are of an Eóganacht lineage. Family roots in Tipperary place them in proximity with the Cashel Eóganacht when they were at their height of power. A Mulcahy has joined us since he matches the South Irish haplotype of the Glens tribe and the Annals of Inisfallen indicate the possibility of an ecclesiastical connection with a Dean Ó Donnchada in 1317 AD.  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.

From the annals, it would appear that the Hy Donnomoii were scattered after they were forced from Cashel in the mid 1000’s, since for the next century they were lost to recorded history. In that time, the various families would have made their way the best they could, though the majority of them probably remained in the Cork/Munster area. By the time surnames came into practice, they could have taken a local surname, but the royal lineage appears to have been taken under the protection of Awly Mór, or perhaps his predecessor, and they assumed the name O’Donoghue along with Awly’s tribe when surnames were taken.

Uí Dhonnchadha of Ossory

There are two Dunphy’s from Laois who tested to 67 markers to confirm that they are related, which they are.  Initially, they were included in the Eoghanacht Cashel/Glens tribe because of their match to the South Irish subclade as is the Glens tribe.  We 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 upcoming revision of the Historical Origins section (see Rod’s notice in the upcoming July Journal) of the Society website, it dawned on me 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, which also has members that belong with other tribes in the Society project.

The Cavan Group A modal matches that of another established Irish subclade – the NWIMH, the Northwest Irish Modal Haplotype. 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, but David Wilson has reported that the haplotype has been variously estimated from 2,000 years to nearly 8,000 years. 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.

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. 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 (Breifne Group A).

The Cavan Group B has a distinct ancestral modal differing from Group A. It is definitely not NWIMH, but it is quite distinct from the southern Eoghanacht. There is a third Group C with five members in the Society project, and they have more matches in the Breifne Clans’ ‘FD2MaguireGroup’. According to Joe's research, the Donohoes of this group (originally MacDonaghy) are a 15th century branch of the McGuires, descending from a Donnchadh Maguire.

The Cavan Group D are in the U152 subclade. This group of six men are rather close to the AMH except for a value of 10 at DYS 391 (which is the off-modal value of the Glens tribe for that marker) and hence appear somewhat close to the Mór tribe. However, the one gentleman who knows his place of origin in Ireland is from Cavan. Another matching participant in the Breifne Clans project is also from Cavan, though they do not match any other of the Cavan/Breifne tribes. So their haplotype might make it appear that they are not too distant from the Mór lineage.

Hugh Donnachie from the Clan Donnachaidh project joined ours since his haplotype matches these men rather closely, and his TMRCA is also closest to theirs. He has had a Deep Clade test and he is positive for the SNP U152, which places him in the R-U152 subclade. This means that he cannot be related to the Mór lineage in any close time frame, regardless of what his STR markers values are or how close they seem to be to the Mór tribe. We have received the results of a Deep Clade test for another member of the group, and he is also U152+, which supports the probability of the whole cluster being R-U152.

There is also a Cavan Group E now, since two individuals of other surnames have joined the project who match more closely to Donohues than their own surname.  The two Donohues in the group had been in a subset of Group B, but the new members made it more appropriate to give them a separate grouping.

Uí Dhonnchadha of the Déisi Mhumhan??

The largest of our other cluster is defined by the SNP L226 mentioned earlier. For some time, we had postulated that this cluster may have belonged to the Eoghanacht Ruis Airgit. However, researches have recently discovered another clan of Uí Dhonnchadha of the Déisi Mhumhan. 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 a brother to Eoghan Mór, Cas.

Since this L226 cluster matches the Déisi of the O’Briens, it’s possible, and more likely, that this group is of the Uí Dhonnchadha of the Déisi Mhumhan, so we have changed the designation of this cluster to Uí Dhonnchadha of the Déisi Mhumhan?? We will be researching this tribe more in coming months.

There are five O’Donoghues whose family originates in either Offaly or Tipperary. The territory of the Uí Dhonnchadha of the Déisi Mhumhan was in Waterford/Tipperary.

A Dunphy who has joined the project is also Irish Type III. His origins are in Cork back to the early 1800’s. (There is an article about his family in the April 2009 Journal.)

We have a recent participant of another surname - Anderson.  He has no matches with his own surname, but there are matches with the Type III O'Donoghues and other surnames of Dalcassian origins, so he has been allowed to join us.

Teallach Modharain??

There are two occasions when an Eoghanacht tribe was overlord of the Erainn Osraighe tribes of the lands in Ossory, which the Historical Origins link describes as comprising County Kilkenny and certain parts of counties Tipperary and Laois.

The Eoghanacht 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 Eoghanacht Cashel. O’Hart indicates it remained under their control until the end of the 12th century when Normans seized it.

In addition to the Eoghanacht 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 Eoghanacht origins, it is also possible that they were Erainn. In the April 2009 Journal, Eóin Ó Donnchadha 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. Eóin and Kurtis Dunphy (Dunphy origins are said to be in Osraighe, though more on that below) share an unusual allele, and Eóin’s own research uncovered that a number of Carroll’s matched his and Kurtis Dunphy’s uncommon null 425. Initially, that supported a connection between the Ósraighe Ua Donnchadha and the O’Carrolls of Ely, whose territory is in Osraighe.

However, as mentioned in the October quarterly report, 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 425’s (which Eóin and Kurtis share), and there are a tribe of Oriel Carroll’s in this territory. Hence the Carroll’s who are null 425 are probably Oriel O’Carroll’s.

There is a new Family Tree project devoted to the Ely Carroll’s and I’ve been in touch with the administrator. The pedigree of one of the cluster of Carroll’s 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.

Eóin has also researched the Teallach Modharain Ó Donnchadha, of which, as indicated in Rod’s book, little is known. Their territory appears to abut Airghialla tribes, but so far there has not been found any sources which include them in the Airghialla. Joe points out in his BCP Report 5, Part 7 that there are no obvious associations between the Dunphy/Ó Donnchadha names and the Airghialla. In any case, Eóin and Rod are pursuing further research to try to uncover more material which would clarify if the Teallach Modharain Ó Donnchadha may have Airghialla connections. As a result of this additional information, we are listing Eóin and Kurtis as a possible Teallach Modharain cluster at the moment.

Other Clusters

I have labeled 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.

Group I:  I re-evaluated my designation of the previous Ninussa? cluster and concluded that it was not as defensible as I 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 Eoghanacht 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.

Group II:  Melvin Lawrence Donahoo joined the project and his haplotype was rather close to the Breifne Group D just mentioned above. He ordered a Deep Clade test, and I expected he would probably be R1b1a2a1a1b3c1 as well. I was wrong!  He is also R1b1a2a1a1b4 and 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. I’ve placed Melvin in Group II of the Clusters, with another more recent member who matches as well.

Group III: A pair of individuals who match each other with a null value at DYS439, listed as a 12 in the spreadsheets. There is a research ‘null439 DNA Project’ ( at Family Tree that contains over 150 individuals that share this unusual value. It has recently been discovered that a null value at DYS439 is related to the presence of an SNP nearby on the chromosome, which interferes with the test process and prevents a value for DYS439 from being detected. This SNP is L1, which defines the R1b1a2a1a1a3 sub-clade. This subclade is seen mainly in the south and central parts of England, with a presence in Germany which has been interpreted to be its origin. We are not sure how that applies to our participants.

The Group IV participants are known relations - uncle/nephew.

Three members of Group V match the Leinster modal haplotype, so the Leinster modal is included for reference.  One participant has tested positive for L159.2, the defining SNP for that cluster. A fourth member also tested positive for L159, but as described in the section above about Irish SNP's, he is actually positive for another iteration of the SNP - L159.3.

Group VI: 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 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. I think it can be inferred from this that a related group of haplogroup I2a individuals were living in west Cork and affiliated with the Glens Eoghanacht. 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 small group of nine as of yet unaffiliated participants who do not match any of the clusters we have identified. We await more participants in hopes that matches will be discovered.


Overall, we have a growing number of Dunphy’s in the project, and their genetic distance indicates 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.


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 yDNA 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 yDNA 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.

Other Haplogroups

We have a few members now who are members of a different haplogroup. While they have the name O’Donoghue, of various spellings, their genetic heritage is necessarily different from the majority of members in identified tribes. There could be various reasons for these differences, such as the discussion of Group V above. There are other participants who belong to haplogroup I2a and one in I2b1.

There are also two in haplogroup R1a, which is most common in Eastern Europe. There is the possibility that when the mythic Gallo returned from Scythia, his entourage could have included local people from the Black Sea area where they appear to have lived. See mention of the ‘Scythian connection’’ in the discussion of the O’Donoghue Mór tribe.

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. RecLOH events are considered to be more stable than STR’s but more mutable than SNP’s. In the spreadsheets, I’ve pointed out with a grey highlight where it appears likely that the allele values are the result of a recLOH rather than mutation.

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 April 2016

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