DNA Genealogy


DNA studies can be used to categorise genealogical groups sharing one common ancestor at one given point in prehistory, through the study of haplogroups. There are two kinds of haplogroups: the paternally inherited Y-chromosome DNA (Y-DNA) haplogroups (i.e. through the male line), and the maternally inherited mitochondrial DNA (mtDNA) haplogroups (i.e. through the female line).


Depending on the depth of analysis, the Y-DNA can determine whether two apparently unrelated individuals sharing the same surname do indeed descend from a common ancestor in a not too distant past (3 to 20 generations) or through deeper analysis identify the ancient ethnic group to which one's ancestors belonged (e.g. Celtic, Germanic, Slavic, Greco-Roman, Basque, Iberian, Phoenician, Jewish, etc.).


In Europe, mtDNA haplogroups are quite evenly spread over the continent, and therefore cannot be associated easily with ancient ethnicities. However, they can sometimes reveal some potential medical conditions.


The following is a ‘sample’ of the genetic make-up of the Y-DNA Haplogroup in Ireland:




R1b Celtic Basque


I1 Nordic Germanic


I2b Saxon Germanic


R1a Slavic


I2a Slavic


E3B Greek


J1 Jewish


G Caucasian


The R1b Haplogroup is thought to be the direct descendant of Cro-Magnon, the oldest Homo-Sapiens settlers in Europe. It is by far the most common in Western Europe, reaching over 90% of the population in some parts of western France, northern Spain or Ireland. The highest concentration of the Celtic R1b mutation (over 50%) by whole country in Europe are:


Wales              82%

Ireland            79%

Scotland          72.5%

Netherlands     70.5%

Spain               70%

England           67%

France             61%

Portugal           56%

Belgium           55%


Denmark, Germany, Switzerland and Italy also have high concentrations. This roughly equates to Western Europe minus the Nordic countries. The R1b haplogroup can further classified to determine the movement of populations over time. R1b1b2a1b6a/R1b1b2a1b6b/ R1b1b2a1b6c (R1b1c1 or R1b1c7) arrived in Ireland 3000 to 2500 years ago.



Origins, age, spread and ethnic association of European haplogroups and subclades


Distribution of European Y-chromosome DNA (Y-DNA) haplogroups by region in percentage


International Society of Genetic Genealogy (ISOGG)



It is important to check the number of markers that will be tested before choosing a test. For example, the Genographic Project (discontinued in 2019) looked at only 12 markers, while most laboratories and surname projects recommend testing at least 25. The more markers that are tested, the more discriminating and powerful the results will be. A 12 marker STR test is usually not discriminating enough to provide conclusive results for a common surname. STRs results may also indicate a likely haplogroup, though this can only be confirmed by specifically testing for that Haplogroups' single nucleotide polymorphisms (SNPs). The test results are then compared to another project member's results to determine the time frame in which the two people shared a most recent common ancestor (MRCA). If the two tests match on 37 markers, there is a 50% probability that the MRCA was fewer than 5 generations ago and a 90% probability that the MRCA was fewer than 17 generations ago.


DNA samples were collected from 1,125 Irish men, bearing 43 different Gaelic surnames. On average, a man has a 30-fold increased chance of sharing a 17 STR Y-chromosome haplotype with another man of the same surname but the extent of similarity between the surname and haplotype varies widely between surnames which is attributed this to differences in the number of early founders. Some surnames such as O’Sullivan and Ryan have a single major ancestor, whereas others like Murphy and Kelly have numerous founders probably explaining their high frequency today. Notwithstanding differences in their early origins, all surnames have been extensively affected by later male introgession. None examined showed more than about half of current bearers still descended from one original founder indicating dynamic and continuously evolving kinship groupings. Mutation rates are not available for all loci, therefore weighting was instead based on the variance in repeat score amongst 985 Y-chromosomes within the discrete R1b3 haplogroup. (McEvoy et al)


There are not enough results with sufficient deails for the Tracey surname to make conclusions but it would appear, as expected, that the majority of results are of Irish origin with some Norman-Nordic and Anglo-Saxon results. There may be a lineage connection for the DYS392=11 mutation, as explained below.


In the Tracy DNA project, there were 27 Y-results for ‘Tracy’ with the following haplogroups:


E1b1a (1)

I2a (2)

R1b1 (1)

R1b1a2 (R-M269) (17)

R1b1a2a1a1b4 (R-L21) (4)

R1b1a2a1a1b4h (L226) (2)


All the R1b Traceys have these two markers in common; No. 6, DYS426=12 which has an incidence of 2% for R1b and No.9. DYS3891=13, which has an incidence of 15% for R1b. However, I have been told that neither of those mutations is particularly significant, especially for R-L21 members.



As testing procedures progress, it is possible to further determine the detail of the haplogroup. The following are the results of further testing:


R1b1a2 (FTDNA) (R-M269) = R1b1a2 (ISOGG)
R1b1a2a1a1b4 (FTDNA) (L21) = R1b1a2a1a2c (ISOGG)

R1b1a2a1a1b4h (FTDNA) (L226) = R1b1a2a1a2c1f2a (ISOGG)


In the Ireland Y-DNA Project, there is the additional result for Treacy and Tracy with the following haplogroup: R1b1b2 (1) I2b1 (1).


On Ysearch there are also nine results with following haplogroups: R1b* (Cork Ireland), R1b1b2 (Great Yarmouth, England), R1b1b2a1b (Ireland), R1b1b2a1b5 (Wexford, Ireland), I2a (Limerick Ireland), G (Unknown).



The Tracy DNA Project?


The Tracy DNA Project was located at World Families, http://www.worldfamilies.net but is now defunct. A reduced version is available at https://www.familytreedna.com/groups/tracy/


The majority of Traceys in the world are of Irish descent. According to the ancient Irish genealogies they are decended from four tribes which were located in the four provinces of Ireland. There are also the Traceys who came to Ireland from England.


By joining the project, you will be providing information which will build up the picture of our ancient descent. Also you will be helping others to determine where in Ireland their ancestors came from. Joining the project is easy. See the Family Tree DNA website for current pricing.  You can test at a lower level to see if you have matches, then upgrade later without taking another sample to obtain more refined results.


In order to generate the best information possible, participants should indicate their earliest known ancestor and location in Ireland, Scotland, England, etc. If you require any assistance, please contact the website info@traceyclann.com


In the Griffiths Primary Valuation property survey of 1848-64, the following are the rough percentages of Tracey households living in each county:




































































Ireland yDNA Project http://homepage.eircom.net/~ihdp/ihdp/index.htm

McEvoy, Brian & Bradley, Daniel G. (2006) Y-chromosomes and the extent of patrilineal ancestry in Irish surnames. Hum Genet. http://homepage.eircom.net/~ihdp/ihdp/documents/ydna_irish_surnames.pdf

McEvoy, Brian; Simms, Katharine and Bradley, Daniel G. (2008) Genetic Investigation of the Patrilineal Kinship Structure of Early Medieval Ireland. American Journal of Physical Anthropology. http://homepage.eircom.net/~ihdp/ihdp/documents/fulltext.pdf

McEwan, John (2006) R1b1c7 haplogroup M222 SNP aka North West Irish Variety, IMH and R1bSTR19Irish http://www.geocities.com/mcewanjc/M222.htm

O’Neill, Edwin B. and  McLaughlin, John D. (2006) Insights Into the O’Neills of Ireland from DNA Testing. Journal of Genetic Genealogy 2:18-26,  http://www.jogg.info/22/ONeill.pdf



Irish Tribal Clusters


In the ancient Irish genealogies of the Bairrche tribe, the Treasaich and Mac Gormáin families belonged to the royal family and were related. Some members of the Tracy and Gorman DNA Projects contain a very rare mutation, DYS392=11. According to Seán MacGorman Powell, the Gorman Project Administrator, after a careful analyses of all DYS392=11 mutation bearers in every major geographical DNA project examined, he identified a total of 79 people worldwide within the R1b haplogroup (and subclades) who bear this mutation. Considering that tens of thousands of R1b people have been tested, it is clear that this represents an extremely rare mutation for R1b, occurring in less than one-half of one percent (< 0.5%) of that major haplogroup. As such, this may be a strong indication of a DNA relationship and may explain the reference to "Macraith, son of Gorman, son of Treasach" in the Annals of the Four Masters for the year 1042 AD. Seán has also compared the Gormans and Tracys who have the DYS392=11 mutation and in his opinion, there is no relation between the two groups outside of the mutation.


Also, within this group of DYS392=11, two members have been tested as belonging to the R1b1a2a1a1b4h haplogroup.


It would appear that the DYS392=11 mutation in the USA comes from a common ancestor, Teague Trassey who emigrated to Virginia around 1655, and whose ancestry has been very well documented.



Gorman DNA Project

History of the Barriche tribe: http://www.traceyclann.com/files/Ui%20Bairrche.htm



The following are Irish Tribal Cluster projects:


NW Irish haplogroup (R-M222) and Irish Type III consider that they have distinctive markers that relate to their clans or tribes.


The North-West (NW) Irish is the signature of the Néill tribe http://www.familytreedna.com/public/R1b1c7/default.aspx


Irish Type III is the signature of the Dál gCáis (west Munster). www.jogg.info/51/files/Wright.pdf  and www.irishtype3dna.org








Autosomal DNA testing is the best DNA test to find relatives of a common ancestor and thereby work out your ancestry. With so many Irish Birth, Death and Marriage records lost forever in the Four Courts Fire of 1922, it may be the only way forward for many of us.  It’s a simple test – you just spit in the tube that comes with the kit and post it back in the box provided. It is purely for genealogical purposes and  reveals no medical traits or information can’t be misused by anyone.

It’s a common test and is offered by Ancestry.com, My Heritage, FTDNA and 23andme. Indeed Ancestry have over 9 million people who have taken their test.


Once your results are processed, these providers will notify you of probable 3rd and 4th cousins who have large segment matches with you and how to contact them and work out the ancestral link. It’s a great first step in deducing your likely ancestry.


HOWEVER, they only alert you to large segment matches (with fairly close relations). What is really exciting is that a new service (absolutely free) provided by GEDmatch.com can alert you to much smaller segment matches with 5th and 6th cousins and you can then attempt to take your ancestry back to the 1780s. With luck and careful thought one can even identify which small segments of DNA are particular to certain families in your ancestry and then you can specifically search for matches with others who have these small segments (ie. you can target your searching for whatever line you are researching.)


More and more people are DNA testing and more and more of these will soon discover the amazing potential of GEDmatch. (Someone I know managed to work out the name of the farmer who got her milkmaid ancestor pregnant in the 1850s! – He happened to be my ancestor!) As the years go on, more and more people’s DNA will be uploaded to GEDmatch and it will become an incredible resource. One reason why so many will be on it is because those keen genealogists who see the potential are hurriedly testing as many relatives as possible and putting their results on GEDmatch. In this way they can identify which segments come from which family lines AND, by testing elderly relatives, can build up the data for going even further back in to history. But you have to act fast and get elderly people to test before they die and all those ancestral clues are lost forever:


You inherit about half your mother’s DNA and half your father’s. ie. 50% of their segments. Your children will inherit half of that (25%). Your grandchildren 12.5% and their children 6.25%. Within another couple of generations, your mother’s  and father’s DNA ancestry will be lost forever.


For the family historian, what you want to do is test all the oldest known relatives and get their DNA ancestral record logged for posterity. They will still have traces of ancestors that are no longer being passed down to your generation.


I want to find the ancestry of my John Treacy born in Athlone in about 1778. I only have 0.78% of his DNA left in my genes. I can test my mum but she only has 1.56% of it. We are both descended from his first child. However, I have used Family Treespublished on Ancestry.com and My Heritage to identify other people descended from John Treacy.  By concentrating on descendants from his youngest child, and then from that child’s youngest child and so forth, I have even found living descendants of John’s who have a significant 6.25% of his DNA still in them. (They’ll also have 3.13% of his parent’s DNA in them and even 1.56% of his grandparents’ DNA  (my 7Xgreat grandparents probably born in the 1740s!!) I hardly yet know how to use GEDmatch BUT, if I can get these elderly far distant “relations” to do the DNA test and get their DNA preserved on GEDmatch now, then I can spend a happy retirement ,in years to come, deciphering that ancestral record. Amazingly, most of these elderly “relatives”- who are in their 90s or even early 100s - but have been more than happy to provide their DNA to help me out!! It’s just this sort of co-operation between families that is spurring-on  GEDmatchusers to test all their elderly close relatives and get the DNA information stored for future use. The more that test the more chance every user will have of finding that critical match that reveals the answers to your ancestry.


Imagine if everyone who visited this amazing Traceyclann site tested their eldest relations and put their data on Gedmatch! We’d all find connections to other Tracey families that go back to the eighteenth century. And some of these families WILL or MAY have family Bibles of baptism records that we can then tap-in to and deduce our own ancestor’s family association from it.

(I’m hoping to identify some of John’s small DNA segments and use them to search for descendants of his younger siblings. Athlone started recording baptisms just four years after John was born – so there’s a good chance that some of his younger siblings did indeed have a baptism recorded there. If I can link to one of their descendants, I will have John’s lineage too. Alternatively, if the link is to a Tracey family from Yorkshire, then I’ll presume he was the son of an English soldier stationed in the garrison town of Athlone in 1778 (then I’ll check the regimental muster rolls for soldiers named Tracey stationed there in 1778.) He had a son called Alexander Barclay Tracey – if I get a small segment match with a Barclay family, then that too might be the vital link.


I urge you all to ponder on how this amazing new genealogical tool (GEDmatch) could be used to deduce your ancestry, and hurry to get your oldest relatives to do the common Ancestry.com/My Heritage /23andme or FTDNA DNA autosomal DNA test NOW  - for your (and my) future use one day!


Many thanks,


Jon Lee

9th May 2018


Any Athlone Tracey families reading this may want to look at John’s known tree on Ancestry.com





Last update: 30 July 2023