Main Findings

The main findings that have emerged from our Study so far are listed below:

1.   The success of this Study is manifest by its steady growth over fifteen years to over 560 participants, so that it is now one of the 50 largest of over 10,000 surname DNA projects worldwide.   96% of the participants have agreed to share their results in public.

2.   Amongst those now tested are descendants, direct or collateral, of the Lairds of Drum, Bonshaw and Castle Irvine, of the Dumfries, Ewesdale and Limerick branches of our surname, and of notable individuals including the American poet Washington Irving (1783-1859), the orator Rev. Edward Irving (1792-1834), and the mountaineer Sandy Irvine (1902-1924).   Representatives of the Cleuchhead, Castelderg, Lancaster Co., Augusta, and Westmoreland Co. branches have also tested.  
3.   About 5% of these participants, including senior representatives of all the long-established Scottish and Irish branches of the surname, have been asked to participate in the Study to enable traditional genealogical relationships to be proved or disproved.  The remaining 95% of participants have joined the study at their own initiative, in the expectation that their tests will identify hitherto unsuspected relationships.
4.   95% of the participants have tested to 37 STR markers or more.  However testing to higher resolutions has generally been found to be less cost effective, and upgrading to 111 markers is not recommended without prior consultation with the Study Administrator.  Up to 838 STR markers are now available to individuals taking the BigY700 test, but these additional markers are of much less value than the more reliable SNP data derived from these newer tests (see below). 

5.   The geographic origins in the Old World of the paternal ancestry of nearly 90% of all participants have been ascertained.  Scottish origins predominate.

6.   Some local spelling variants of the surname remain dominant within Great Britain (Irving in Dumfriesshire, Irvine elsewhere in Scotland, Urwin in Northumberland and Durham, Irwin elsewhere in England). However the spelling of the surname today, especially in Ireland and in the New World, has been shown to be a most unreliable indicator of the geographic origin of paternal ancestry.

7.   To qualify for membership of one of the Study’s genetic families (aka surname branches), comparison of the participant’s DNA signature with the modal signature of the family must have a genetic distance of 6/37 or less, or FTDNA’s 24-generation, no paper-trail TiP must exceed a probability of 90%.
8.   Over 40 distinct genetic families (aka surname branches) using the surname and its spelling variants have been identified, each unrelated to one another during the surname era.   All but seven have representatives today in North America. The number of distinct genetic families in our Study is now increasing very slowly, suggesting that few more large branches of our surname are still waiting to be "discovered". 

9.   Nearly two-thirds of all the Study's participants are members of a single genetic family, sharing a common ancestor who probably lived in Dumfriesshire on the Scottish Borders during the 14th century, although his name is unknown.  This "Border Irwin" family includes participants representing the Irvines of Eskdale, the Irvings of Bonshaw and of Dumfries (all in Dumfriesshire), the Urwins of Durham and Northumberland, and the Irvines of Castle Irvine (Co. Fermanagh).  Some of these participants still live in Dumfriesshire, some are descended from ancestors who migrated direct from there to USA, but the majority now living in USA are descended from ancestors who probably migrated from the Borders to Ulster in the 17th century, and from Ireland to colonial America (typically to the piedmont regions of PA, VA, NC, SC or GA) in the 18th century, typically for religious or economic reasons.  This proportion of participants sharing a single common ancestor within the surname era is higher than found in most other Scottish surname DNA projects, and our Borders genetic family is probably the largest such family in any Surname DNA project.  

10. A curious feature of this large genetic family is that 30 participants have identical STR signatures to 37 markers (and 12 of which have identical signatures to 67 markers), and yet very few of them have been able to identify a genealogical relationship.  However these signatures have some differences in the 68-111 marker panel.  SNP tests now suggest that this apparent uniformity at 37 and 67 markers is probably due to convergence, and so is misleading.  

11. Conversely this family has two brothers with a genetic distance of 2 in 25 markers.  This example illustrates the dangers of relying on the STR signature of a single participant to represent a genealogically related family.  

12. All of the remaining Irwin genetic families in the Study are represented by only a few participants:  the largest has only 14 participants.

13. Nearly half of these small genetic families, all of whose members now use the surname Irwin (or spelling variants), share the DNA signatures of other surnames, mostly from the Scottish/English border, implying some non-paternal event ("NPE") such as a young boy taking the name of his Irving stepfather, probably before the 17th century when many Irvings migrated to Ireland.

14. A further eight of these small genetic families have origins elsewhere in Scotland, including one from Drum in Aberdeenshire, one from Forfarshire, one from Perthshire, two from Orkney, and three from Shetland.  None of these families are genetically related to one another or to the Borders family within the surname era, and lack close matches with any other surname.  This suggests most are not NPEs but are descended from unrelated individuals who adopted the surname independently at an early date, possibly because their earliest ancestor came from the town of Irvine in Ayrshire, which was an important port in medieval times. 

15. The specific finding that representatives of the families of Bonshaw and Drum do not share a common paternal ancestor during the surname era contradicts the tradition that the two lines were related in the 14th century through a paternal line.  However it remains possible, although there is no supporting evidence, that the two lines were related by some female line.

16. None of the participants share the DNA signatures of the Carlyle, Dunbar, Hume or Robertson families whose traditions, like that of the Irvings, claim paternal descent from Crinan, the grandfather of King Duncan I.  There is thus no DNA evidence to support the tradition, now also unsupported by any documentary evidence, that the Irvings had royal ancestry

17. It is accepted that the probabilistic basis of genetic genealogy prevents dogmatic conclusions, and that genetics alone cannot disprove long-established traditions. 
18. The origins of a further twelve small genetic families have not yet been determined; all are probably Scottish; some may be NPEs.

19. These findings are suggesting that even within Scotland the surname has plural origins. This challenges the tradition that all Scots bearing the surname had a single ancestor.

20.  Ten other small genetic families appear to have non-Scottish origins:  four apparently use anglicised versions of Gaelic surnames that originated in southern Ireland, two appear to be descended from the Dutch or German surname Arnwin, and one has African origins.

21. 10% of the participants in the Study have clearly inherited the DNA signature of the relevant Irwin genetic family but are no longer using the surname Irwin (or variant spelling).   The ancestries of these participants are clearly include NPEs.  Probable circumstances, locations and approximate dates for some of these "events" have been identified.  

22. Only 7% of all participants cannot (yet) be unassigned to a genetic family because they are singletons apparently unrelated to any other participant.  Some of these will be NPEs.

23. So far there has been only limited success in identifying genealogical relationships within our genetic families, but this is not surprising as only about 0.5% of the world's 100,000 adult males who today use the surname, however spelt, have undergone a yDNA test.  As new participants continue to join, and analysis methods improve, more relationships will be found.

24. These developments, together with FTDNA's predicted haplogroups of participants who have not undergone SNP tests, has enabled all of the Study's genetic families to be placed on a Clan Irwin haplotree (aka phylogenetic tree, or genetic family tree) which shows the descent of each genetic family, and hence its members, from the genetic "Adam".
25. A small number of participants in our Study have opted to take National Genographic's Geno2 test, but the results have contributed little to our Study. 
26.  Two attempts have been made to sub-divide our large Borders genetic family into sub-groups.  In 2011 the family was tentatively divided into 14 sub-groups, each with a distinctive STR signature.  Some of these sub-groups were assigned a local geographic origin, and some an approximate age.  The sub-groups were identified with the help of cladograms (both phylogenetic trees and network diagrams).  However SNP tests are now showing that while STR signatures are reliable for identifying distinguishing between genetic families they are not a reliable tool for dividing these families into sub-groups, and so SNPs now form the basis of our second, current sub-division.  
27. The L555 SNP, almost unique to our Borders genetic family, was discovered in 2011, thanks to the initiative of one of our participants.
28. FTDNA introduced their Next Generation Sequencing BigY test in 2015.  Six of our early BigY tests were funded in part or in whole by donations by a few most generous participants.  Although interpretation of the SNPs identified by early BigY test results initially proved difficult, a methodology has been developed independently that is giving interpretations of BigY data that was compatible with the work of leading L21 "citizen scientists" including Dennis Wright, Mike Walsh and Alex Williamson. 
29. As of  April 2021, 77 participants have taken FTDNA's BigY test, of which 65 are BigY700 and 63 are L555 positive.  A further 9 BigY tests are on order. 
30. Analyses of these L555 BigY tests suggests that the Border surname probably dates from the early/mid 14th century, roughly as expected from contemporary records. 
31. Building on the results of our BigY L555 results, FTDNA launched their L555 SNP Pack test in April 2016.  This tests for 86 SNPs contemporary with or downstream of L555.  This test enables members of our large Borders genetic family who have not taken the BigY test to determine which of SNPs they share with those who have taken the BigY test.  Over 80 participants have taken this test, some of whom later went on to take a BigY test.
32.  Analysis of the BigY and L555 Pack tests together have enabled the construction of a L555 haplotree with over 60 branches  with up to 6 biforcations between L555 and "private" SNPs.   This tree continues to grow as more L555 Irwins take these tests.
33.  More specifically, these tests have enabled distinctive SNPs to be identified with the Bonshaw and Castle Irvine lines, and this triangulation means that the haplotree of mankind can now be extended down to within pedigrees derived by conventional genealogy - perhaps the "holy grail" of genetic genealogy.  The Study is one of a very few that have so far been able to do this.
34.  Building on the lessons learnt from this Study as the Administrator thereof I have been privileged to be asked to lecture at a number of genetic genealogy conferences/fairs in England, Scotland, Ireland and USA.  These occasions have enabled me to keep abreast of emerging developments in genetic genealogy and at the same time enable others to learn from our Study.  I have also consolidated several decades of research into our surname into three recently published books which complement this Study and add historical background, particularly to the Irvines of Drum and the Border Irwins. 

35.  While much has already been revealed, including some surprises, about the origins of our surname and its genetic families and their sub-groups, it is clear that considerable further understanding will result from the efforts of individual participants to improve their paternal pedigrees and from the rapidly evolving field of genetic genealogy, and of further L555 Irwins taking BigY or L555 Pack tests.

36.  The Study respects the diverse contributions of all participants to the Study, the Clan Irwin Association and the clan and its heritage.  It continues to welcome all new participants around the world who share our surname, however they may spell it, whatever their origin, and immaterial of the length of their paternal pedigree, as well as individuals who share our DNA but not our surname.  Through the generosity of some existing participants, generous contributions by existing participants to the Study's General Fund is enabling financial assistance to be made enable new participants with long paternal pedigrees to join our Study.

37.  The Study's Privacy Statement and other administrative arrangements are intended to comply fully with the European Union's new General Data Protection Regulation, ISOGG's Interim Guidance on GDPR, and FTDNA's Terms and Conditions.   The new GDPR regime has not resulted in the loss of any participants from our Study, and 96% of our participants have opted to share their results in public. 
38.  The on-going success of this Study is attributed to the technical and financial support given by a number of its dedicated participants, to the support (non-financial) and publicity given by the Clan Irwin Association, by several members of the International Society of Genetic Genealogists, and by the staff of FTDNA, to the regular publication of detailed analyses of test results, and to our good fortune of inheriting a surname with such interesting genealogical and genetic features.
39.  The Study has been placed in its genealogical context in the comprehensive book The Irwin Surname: its Origins, Diaspora and Early Branches, published in 2020.  

James Irvine, Study Administrator, May 2021