McCarthy Surname Study- Background

McCarthy/MacCarthy is one of the most common surnames in Ireland today and is prevalent throughout Counties Cork and Kerry.  Through migration over the past four hundred years, McCarthys now reside in many countries throughout the world.

In October 2002, the McCarthy Surname Study was started through Family Tree DNA, Inc. (FTDNA) of Houston, Texas, U.S.A. The McCarthy Surname Project will attempt through Y-DNA analysis to compare individuals with surnames common to the McCarthy Clan and to identify any genetic markers which might single out groups of McCarthys or their immediate predecessors.  These surnames include but are not limited to the following: McCarthy, MacCarthy, Macarthy, McCarty, and McCarter.

Apart from facilitating family connections among McCarthys throughout the world, it is hoped to identify the yDNA profiles associated with both the leading families of the various MacCarthy septs (Mór, Reagh, of Muskerry, of Dunhallow, Glas etc.) identifiable in the ancient histories as in use from ca. 14th century and more recent agnomens (or leash- or nick- names) adopted to distinguish one McCarthy family grouping from another e.g. Cnoic, Crimeen, Cruig, Daunt, Farshing, Guidagh, Rabagh, Sowney.

As more data becomes available, the findings of this and other projects for surnames which the ancient histories and genealogies indicate derive from first millenium A.D. Eóghanacht origins can be compared with the content of these writings.

McCARTHYS IN ANTIQUITY
Original - 10 May 2010.
Last updated – 29 September 2011.

1        Introduction

The following is written by an amateur genealogist and historian with a view to providing useful information for members of the McCarthy Surname Study, some of whom may be more knowledgeable, some beginners. The author will be happy to review, and correct where justified, any perceived errors. A modicum of understanding of DNA diversity is assumed: please refer elsewhere on the FTDNA website or to the most helpful ISOGG (International Society of Genetic Genealogy) website for the science of SNPs (Single Nucleotide Polymorphisms), the phylogenetic tree, STRs (Short Tandem Repeats), DYS (DNA y-chromosome Segment) values / alleles, the distinction between a haplogroup (of which clade or subclade are used to indicate subdivisions in the following) and haplotype, and their use in genealogy. And, since your interest is in McCarthy ancestry, you must of course absorb all that the Ireland yDNA (formerly Irish DNA Heritage) Project website has to offer.

2        Brief history

The earliest evidence of homo sapiens in Ireland is from ca 8,000 B.C, when it is believed he entered present day Co. Antrim from south-west Scotland, either by boat or via the landbridge still remaining as the last ice age closed and the sea levels were still rising.  Throughout the Mesolithic and Neolithic periods (ca. 8,000 - 2,000 B.C) it seems probable that the inhabitants of Ireland were, as those of Britain, the descendants of those who had retreated towards the Iberian, in particular, and Italic peninsulas during the last Ice Age and the peoples who already occupied these warmer climes, along with any new waves of migration from south-east Europe. YDNA haplogroups E1b1, I1, J1 and J2 could have abounded. Megalithic tombs were rare in the extreme south of Ireland, suggesting that the south of Munster was more thinly populated than the north in the Neolithic Age.

The most difficult aspect of Irish genealogy for many is the lack of parish records much before 1815 in rural areas and the later 1700s in the major towns. However, although following a paper trail back through the 18th century may be impossible for many, what lies beyond is a unique store of genealogical information stretching back many centuries. It was the custom of the peoples who occupied Ireland 2,000 or so years ago to designate a member of each community (or “tribe” or “family”) who would learn, remember and recite its genealogies. Early in the first millennium, these began to be written down. In due course the earliest writings were lost, but successive copies retained the information, albeit flavoured with mythology, distorted by inventiveness or corrupted by political correctness. Certainly from the time of early Christianity in Ireland (the 5th century A.D.), when monks began to take on the role of the scribe, the genealogies were woven with biblical connections, placing them in a context which tied together all strands of known history. But whether fact or fiction, we do have a lineage claimed to have produced the leading McCarthy families and which goes back before these earliest written genealogies.

The McCarthy name itself derived from Cárthach, the King of the Eóghanachta of Cashel, who was killed by the Lonergan clan in 1045 (ref 1), and pedigrees have been published displaying the many branches of the family deriving from his grandsons Tadhg (Timothy) and Cormac – there was possibly also a brother Donncha (Denis) - dividing in subsequent centuries into a number of “septs”. Cárthach's son, Muireadhach mac Cárthaigh (son of Cárthach), was the first to adopt the surname of McCarthy (as it is most commonly anglicised these days).

Written sources from about the 12th century onwards indicate that this McCarthy family derived from the Eóghanachta of southern Ireland, who are claimed to have also spawned the McAuliffes (from the above Tadhg), McGillycuddys, O’Callaghans, O’Donoghues, O’Keefes, O’Mahonys, O’Sullivans and others. The Eóghanachta took their name from the third century A.D. Eóghan Mór (Eugene / Owen the Great), son of Olioll Olum, King of Munster. However it is suggested that the identity “Eóghanachta” only came into being following the era of Eóghan Mór’s gt gt grandson (Conall) Corc, in the 5th century A.D. On the death of King Olioll Olum, his kingdom was allegedly divided into Desmond (south Munster), ruled by Eóghan Mór (or a son thereof), and Thomond (north Munster), by Eóghan’s brother, Cormac Cas (from which the term dál gCais, or Dalcassian, is derived to describe its peoples). However many consider this story has been fabricated at some stage to provide the image of a unified population. Certainly the genetic signatures of those who it is suggested have 'Eóghanacht' and 'Dalcassian' y-DNA haplotypes (see references to SNP L226 and Irish Types II and III below) are not consistent with common ancestry as little as 1,500 years ago. The case for maintenance of a continuing blood line in the Eóghanacht, Dalcassian or other similar lineages lies in the primogeniture practiced under Brehon Law, which continued until the dismantlement of the Gaelic order at the end of the 17th century. Each new king, chieftain or chief was supposed to be elected from within the blood line. Thus each of the various McCarthy septs, such as the McCarthy Mór in Co Kerry, McCarthy Reagh (Riabhach) based at Carbery, the Dunhallow McCarthys, in north-west Cork, McCarthys of (East and West) Muskerry, and McCarthy Glas of Gleannacroim (in the vicinity of Dunmanway), are shown on ancient pedigrees as tracing back to Cárthach and Muireadhach.

3        Diversity among McCarthys

SNP testing reveals McCarthys in haplogroups E1b1b1a (E-M78), I1, I2a and I2b1, as well as the more common R-M269 (FTDNA’s R1b1a2), but notably, so far, none others. Like R1b1a2, the I* clades prevail not only in Ireland, but also in Western Europe, I1 being prominent in Scandinavia, and I2a in several locations in Southern Europe. E1b1b1a is believed to have appeared in N. W. Greece about 8,500 years ago and its subclades have strong Mediterranean / Adriatic connections (ref 2). The E and I haplogroups had gone their separate ways well before the last ice age, so clearly their members cannot be traced to the same 3rd century male ancestor as those of R1b1a2, even if they may by that time have been living side by side in the same population group.

As indicated below, haplogroup R1b1a2 (R-M269) arose in the same era as E1b1b1a, but significant differences in the haplotypes of our R1b1a2 McCarthy members are proof that these too comprised a number of different lineages each with their own origins – common ancestors - long before the time of King Olioll Olum. The Trinity College, Dublin, Irish DNA project of around 2003/04 by D G Bradley and B McEvoy identified through STR testing that many O’Neills and carriers of other surnames common in north-west Ireland appear to descend from two particular common ancestors, and that calculations of the time to the more distant of these was consistent with him being the legendary Niall of the Nine Hostages (ca. 400 A.D.). But others of these same modern-day surnames clearly did not share these ancestries. A similar situation exists for the name McCarthy and its variants. A surname could have been assumed for several reasons, other than direct male descent, e.g., in the case of McCarthys,

•Soldiers, serfs, or slaves or hostages taken in battle and who remained with their captives, all under the tutelage of a McCarthy king, chief of chieftain, could have adopted this surname.

•Foreign raiders such as Vikings being absorbed, a century or two after they settled in Ireland, into the group which became the McCarthy family as they became “gaelicised”,

•Adoption, much as we know it today.
•Stepsons taking the McCarthy name of their new stepfather (early deaths of husbands or wives, and thus remarriages, were common).
•The sons of Cárthachs other than he who died in 1045 forming their surnames in a similar manner.

4        In search of the Holy Grail, a defining SNP

Estimates of the age of SNP R-M269, the prime marker for haplogroup R1b1a2, range from 4,000 – 9,500 years. Three or more SNPs later (“deeper”) along a lineage derived from M269, the phylogenetic tree divides into the parallel branches identified by SNPs R-P312 / S116 (Note 1) and R-U106. Many McCarthys belong to the R-P312 branch but we have at least one member (a "McArthur", who may, of course, not have McCarthy origins at all) on the R-U106 branch. Among the various subclades of the haplogroup that SNP R-P312 currently defines is that identified as SNP R-L21 / S145, recently relabelled R1b1a2a1a1b4 by both FTDNA and ISOGG. Dr A Klyosov believes this originated in the Rhineland or west thereof about 4,200 years ago (ref 3), with its carriers first arriving in Ireland about 3,500 years before present (ybp). Many Irish men have tested positive for L21. As SNP testing goes “deeper” and “deeper”, mutations are being discovered which, it seems, must have occurred after arrival in Ireland. The holy grail would, of course, be to find an SNP which occurred not much short of a thousand years ago at the birth of a McCarthy ancestor whose progeny flourished. A number of recent SNP discoveries, all known to be “children” of R-L21, have strong associations with Irish peoples. These include:

• SNP R-M222, which has been observed in many peoples of north-west Ireland.

• SNP R-L226 / S168, discovered in 2009, and  identified in over 80 samples, most of which relate to people or names with northern Munster connections. This was the homeland of the aforementioned Dalcassian peoples.
• SNP R-L159.2, which has a fairly strong association with the Irish, but quite a few lines with a positive result for L159 have also been traced to Scotland, England and possibly even European locations.
• SNP R-P314.2, also discovered in 2009, which has only been positively identified in 24 men to date, with prediction in a further approx. 85.  A distinct “base” or "modal" haplotype which appears to be associated with R-P314.2 is present in about 30% of all McCarthys who have undergone STR testing under the Trinity College or FTDNA Projects. A further SNP, R-L362, identified late in 2010, occurs subsequent to P314.2 in a branch of this lineage….and appears to fall within the "holy grail" category since it is on this branch that all the P314.2 predicted or tested McCarthys are found.

The initial results of the first full genome sequence of an Irishman were published on 7th September 2010 and it is hoped that their analysis will in due course provide some new y-DNA SNPs for which others may test. Irish Type II haplotypes (see section 5 below) from two other projects were sequenced late in 2010 under the “L21 Walk Through The Y” Project but although one of these revealed a new SNP, R-L459, it seems this occurred at a time close to that of R-L21 and thus does not afford any significant subdivision of R-L21 folk.

5        Use of STR alleles in determining historical origins

Pending the progress of the phylogenetic tree to the point at which SNPs which must have occurred within the past one or two millennia are irrefutably located thereon, much energy has gone into extending use of y-DNA STR DYS values to characterise population groups. In the sphere of our interest you may come across hypothetical “modal haplotype” sets of STR DYS values (alleles) assigned to particular geographical areas or populations. The following are relevant to Irish research.

a)        Super Western Atlantic Modal Type (SWAMH): most evident in the Iberian Peninsula and Ireland, then Britain (See, e.g. Ysearch 55GU9).
b)        SNP L21 / S145, as described above. This is almost identical to SWAMH,
c)        (North-western) Irish Type I: now associated with the above M222 SNP. (Ysearch M5UKQ).
d)        (South) Irish Type II. (Ysearch Z9HCX). This type is very common in studies of surnames supposedly stemming from Eóghanacht families. About 20% of McCarthys fall into this category, although others may derive from early (i.e. Bronze Age) branches of the lineage. Key allele values are DYS 391 = 10, DYS 385b >14, DYS 439 = 11, DYS 447= 24, DYS 442 = 13 (although 12 is also common) and DYS 565 = 11.
e)        SNP P314.2 modal haplotype, as described above. Key allele values are DYS 390 < 24, DYS 388 = 13, DYS 439 = 13, the difference between DYS 389-2 and 389-1 < 16, DYS 570 = 18, DYS 460 = 10, DYF 395Sa1 = 16, DYS 406S1 = 11, and for McCarthys, DYS 557 = 17, DYS 617 = 13.

f)        Irish Type III: associated with the above L226 / S168 SNP, labelled rightly or wrongly as the Dalcassian type (Ysearch NT4BZ).

g)        Irish Type IV / Continental: possibly a type introduced into Ireland with the Norman invasion (from 1169). (Ysearch UWM64).

References

1.        Annals of the Four Masters (Micheál O’Cléirigh and others, 1632-36).
2.        Eupedia website (http://www.eupedia.com/europe/origins_haplogroups_europe.shtml#E)
3.        Various papers, articles and correspondence of Dr Anatole Klyosov to be found on the web. (Since the subject is progressing fast, specific citings are avoided lest they become superseded!).
4.        Fresh analyses of McCarthy results in relation to those of other Southern Irish surnames appear in updates of the Results page in 2011 on this McCarthy Study website and / or at the McCarthy Surname Project discussion page at WorldFamilies.net.

Notes

1.        SNPs are denoted with a letter identifying the laboratory which discovered them plus the laboratory’s allocated reference number. Where two (or more) laboratories have made the same discovery, both numbers are quoted, in alphabetical order.
N. McCarthy