4. Interpreting Drum's DNA Test Results

James M Irvine, December 2008
One of the original goals of our Study is “To identify DNA profiles of the Bonshaw and Drum branches and sub-branches thereof”.  We have had the Bonshaw profile for some time now, and I am pleased and most grateful to be able to report that we now have the results of the full 67-marker yDNA test of a senior male descendant of the Drum line.

The reason for our interest in the DNA profiles of the lines of Bonshaw and Drum is of course the tradition, dating back to the manuscript account of The Original of the Family of the Irvines etc. written by Dr. Christopher Irvin c.1678, that the two lines had a common ancestor.  The account relates that William de Irwyn, who was given the forest of Drum by Robert the Bruce in 1323, was a son of Bonshaw.  There is thus an expectation by most participants in our Study that the DNA profiles of the two lines would show a close match. 

A few of the participants in our Study, like myself, have inherited a tradition that we are descended from the Drum line, and so have an added expectation that our individual DNA profiles will show a close match to that of Drum.  Some of these participants are in the Borders Group, but some are not, and nor do they share similar DNA profiles.  It was therefore going to be inevitable that most of this latter group were going to be disappointed.

Hence it is with considerable surprise that it now transpires that the DNA profile of the senior Drum line does not match the DNA profile of any other participant in our Study, or indeed of anyone in the Ysearch database.  The purpose of this note is to forewarn participants of this development, and to discuss the implications arising.


The closest matches between the recent Drum DNA test profile and those of other participants in our Study show genetic distances (or mismatches) of 3/12 (with an associated 24-generation TiP of 35%), 15/36 (19%), and 21/67 (5%).  The closest matches in Ysearch, regardless of surname, are at least 3/12 and 4/36.  At face value this result implies that the present senior male representatives of the Bonshaw and Drum lines today do not share a common male ancestor.

This is not the first time the traditional relationship between Bonshaw and Drum has been questioned.  As early as 1672 Sir George Mackenzie suggested in his manuscript Families of Scotland that the Irvines of Drum took their name from the town of Irvine in Ayrshire.  Recently Professor Duncan suggested that the Chancellor Bernard who may have been the mentor of the first William of Drum may also have been the Abbot of Kilwinning, just three miles from the town of Irvine (Acts of Robert I 1988, 202, 210, 488, 514).  It has thus been inferred that the first Irvine of Drum might have come from that town.  Although there are records of Irvings in Dumfriesshire as early as 1376, modern research has also shown that, apart from Dr.Christopher’s manuscript and accounts derived therefrom, the earliest surviving contemporary reference to Bonshaw is not until 1484.  And contrary to Dr.Christopher’ account, we now know the laird of Bonshaw did not die at the Battle of Flodden in 1513.  It may also be relevant that The Original of the Family of the Irvines was written over 300 years after William of Drum is said to have left Bonshaw, and at a time when historians were respected more for the style in which they wrote than their attention to historical detail. 

The recent DNA result is thus further evidence that suggests the traditions recorded by Dr.Christopher need to be investigated further.  But on the other hand it would be wholly inappropriate to now jump to the conclusion that this single DNA result proves Bonshaw and Drum did not share a common ancestor, as tradition suggests.  Several additional important considerations are relevant:

First, it has recently become apparent that even before Dr.Christopher’s time there seems to have been an acceptance that Bonshaw and Drum shared common ancestry:  both lines had been using holly leaves in their heraldic arms since before 1600, and in 1588/9 it was suggested that the 8th Laird of Drum should stand surety for the Irwings of Annandale (Register of the Privy Council iv, p.356).  The use of similar heraldic devices and the standing as a guarantor of a namesake were both practices indicative of consanguinity.

Second, Dr. Christopher was appointed by King James VII as his Historiographer in Scotland, and despite criticisms that can be made of his account of 1678, his text contains few details that can be proved false.  Indeed it is only relatively recently that his claim that the first William of Drum was the King’s secretary has been corroborated by the recognition that contemporary records confirm his having been one of the King’s clerks. 

Third, most of the many subsequent histories of the family are based on Dr.Christopher’s account.  In particular he and his manuscript were accepted by the Lairds of Drum for many years:  he had been careful to avoid any claim that the Bonshaw line was senior to that of Drum (“whether he [William] was the eldest brother or what brother he was is not known”), and in 1688 he was chosen to serve on the jury that ‘served’ (i.e. confirmed) the 12th laird as heir to Drum (Mackintosh’s The Irvines of Drum 1998, p.221).  Subsequent lairds of Drum promoted his account of their connection with Bonshaw, for example their contributions to Nisbet’s System of Heraldry in 1742 (Vol. ii, App. 66), and to Burke’s Landed Gentry from 1850 to 1976.

Fourth, it is still quite possible that Bonshaw and Drum were related as Dr.Christopher recorded, but there was some later non paternal event (see www.clanirwin.org > DNA Study > Interpreting Results) in one of the two lines that resulted in the relationship passing through a female line.  The pedigree of Drum is well documented apart from the period 1333-1393, but the pedigree of Bonshaw is a blank between the tradition of the early 1300s and the corroborated descent since c.1500.  It is a well established principal in Scotland that the chiefship of an ancient clans can be transmitted through an heiress to her husband after he has adopted her father’s surname.  The chiefship of the Lundin family is one well-documented example of the chiefships of several families that have passed through a female line.  Note however that although the lairds of Drum adopted the surname Forbes Irvine from 1810 to 1976, this usage was prompted by the inheritance of the Forbes lands of Schivas rather than having had anything to do with the paternal line.  Certainly the new Drum DNA profile does not match the Forbes DNA profile.
PS May 2015.  The chances of there having been a NPE in either the Bonshaw line or the Drum line have receded considerably since the above paragraph was written.  We now have DNA confirming the Drum genealogy back to c.1500, and while the Bonshaw line lacks an earlier genealogy the number of Border Irwin DNA tests, coupled with the BigY findings, strongly suggests no NPE in the Bonshaw line back to c1300. 
Fifth, it seems strange that the Drum DNA profile matches no other, even though there are no surviving cadet lines of Drum with a corroborated pedigree. (PS No longer true - we now have the corroborative of a cadet line with a pedigree back to the brother of the 8th Laird.  The Irvine-Fortescue family of today, for example, represents a female line.  It may also be relevant that although Dr.Christopher claimed the Irvines of Orkney descended from the Irvines of Drum, the DNA profile of our small Orkney group does not match that of Drum.  FTDNA advise that in circumstances such as these a further yDNA test of a near relative is always beneficial.  A second cousin of Drum has now agreed to take such a test, and an apparently unrelated Irvine living in Aberdeen has also agreed to be tested.  These tests are being financed from our Study’s General Fund. 

Until the results of these further tests become available the result of the first test is being withheld from FTDNA’s published database, and from the CIA website.  This delay is intended to avoid the propagation outside our Study of premature conclusions, and to give Study participants early opportunity to digest the implications arising from these developments. 


From the above it is apparent that even if and when Drum’s DNA profile is confirmed, it now seems unlikely that DNA alone will ever be able to provide a “cut and dried” answer to the question of whether or not Bonshaw and Drum share a common ancestry.  In other words, those wishing to continue to believe this tradition may legitimately to do so, while those preferring to think further investigation is warranted may do so too!

The associated uncertainties may become less confusing in the future as further participants join our Study.  Such progress would be accelerated by donations to our General Fund so that DNA testing can be proactive rather than just reactive – I have several ideas on possible participants whose involvement might help develop this aspect of our Study.

Meanwhile there is no reason why this development should lead to any discord within the Clan Irwin Association, which has always recognised the individuality of the lines of Bonshaw and Drum.  Nor need it affect the bonds of heritage, goodwill and mutual respect that extend between its members, including its Patron, David Irvine of Drum.

PS  Since this was written we have received several STR test results confirming that the paternal Drum line is clearly not related the paternal Bonshaw line during the surname era.  We have also had a SNP test result that shows we have to go back about 4,000 years to find the common ancestor of the current representatives of the Drum and Bonshaw lines, rather than about 700 years, as the tradition relates. 
It is now clear that EITHER the two paternal lines were never related during the surname era OR in one or other of the two lines there has been a Non Paternal Event.  However DNA tests confirm that there has been no such event in either line since c.1500, and that it is most unlikely there has been one in the Bonshaw line since the 14th century, while the genealogy and heraldry of the Drum line suggests its descent is also robust.
JMI, January 2016.