MacGregor DNA Project - update January 2015
This year's DNA update will move away from discussing Y
chromosome results as I have done in previous years to consider the other tests
currently available. This year there have been 49 new members of the project
whose names reflect the aliases adopted by members of the clan or sept names (such as Magee, Gragg, Greer, or Black)
associated with the clan, and many of the results published this year were for
tests other than the male Y chromosome test (in fact, in total there were over
a thousand pieces of genetic data
reported). Most males who join the project will first do the 37 marker Y
chromosome test. If they find that they match someone else with 35, 36, or 37
markers being the same, it can be useful for establishing familial connections to
increase the number of markers to compare, up to 67 or even 111 instead of just
37. However there are limitations to the use of STR (Short Tandem Repeat)
markers, as they are known, in that DNA mutates randomly. As a result some
testees find that their Y DNA is very similar to that of another male, but
neither person's DNA has mutated very much in 600 years, and as a result what
looks like a recent relationship with another person from the same family
branch is probably simply an indication of connection with the common ancestor
from whom that surname developed as many as 600 years ago. On the other hand, some
distinctive mutations - for example in the project all Stirling/MacGregors have
'16' at DYS576 whereas the norm for the group is '18'- probably indicate
descent from a more recent common ancestor.
When surnames
are grouped together by variant spelling (e.g. Greig, Gregg, Grieg, Grig etc)
it quickly becomes clear that there are multiple origins for these names. Some
of the results in these groups suggest a connection with the main MacGregor
group that predates the actual founder (Gregor) who, it is believed, flourished
c1360, rather indicating a strong genetic connection pre- surnames. What also
emerges, in some cases, is an indication of contradictory genealogy - individuals with very different genetic
profiles who are supposed to be from the same ancestor. Such cases suggest that genealogies need
further checking for accuracy.
It has
been noticeable this year that there has been an increase in interest in the
other DNA tests available as participants seek to learn more about their
genetic descent. In order to help with the interpretation of these, or simply
to help with choice, this blog update will concentrate on some of the more
common: Family Finder (also known as My Origins, Ancestry Painting, All my
Ancestry and so on, depending on the company used); MtDNA (mitochondrial DNA);
and SNP testing. I will deal with each
in turn.
Family Finder/My Origins/Ancestry Painting
This test is designed to give participants an indication as
to the origin(s) of their genetic ancestry. Most geneticists believe that human
beings emerged out of Africa perhaps 70,000 to 100,000 years ago, but this test
looks for more recent connections than that. For those whose later ancestry is
British the test usually indicates a predominance of DNA from the British
Isles, with reasonably high proportions coming from Scandinavia and/or the
Mediterranean. These can usually be explained by links with Viking invaders in
the case of Scandinavia and with emigration from the Spanish ice age refuge, as
well as the possible influence of invasion by the Romans and their soldiers
after AD43.
The results of such tests are often expressed in
colours located geographically like this anonymised one from FamilyTreeDNA:
Fig. 1: My Origins
geographical plot from FtDNA
All the companies which offer this test use the same
principle for presenting results, that is, to show the results as
percentages. Here are the results for
the same individual from 23andme.
Fig. 2: Genetic
ancestry percentage chart from 23and me
Although the results show some variation (for example in
FamilyTreeDNA 3% Middle Eastern against 1.1% Ashkenazi in 23andme) they are
essentially the same. 23andme also show these results as Chromosome View
concentrating on the past 500 years - and this has been highly rated by users. Here
is the same information as Fig. 2 but in the chromosome view.
Fig. 3 Chromosome
view of Fig. 2
BritainsDNA [aka ScotlandsDNA] adopt a colour graph approach
which is a bit different from the others just mentioned but tends to produce
similar overall results. These graphs are obtained by comparing sections of a
person's DNA with the same sections from individuals in known populations. There
are two versions - Figure 4 is based on a global analysis of the DNA, while
Figure 5 refines the European elements of the global report. Note, however, that these results are not
from the same individual as the first three examples.
Fig. 4: BritainsDNA
Ancestry Painting - global result
Fig. 5: BritainsDNA Ancestry Painting - European
And the same company's presentation of chromosome painting:
Fig 6: BritainsDNA
Chromosome Painting
As more data are made available to geneticists, charts and
grids such as these will be refined and developed further. FtDNA, for example, uses
the results from My Origins to suggest relationships between individuals on the
basis of shared DNA segments.
MtDNA - Mitochondrial DNA
Mitochondrial DNA is passed from a mother to her sons and
daughters but only the daughters can pass it on afterwards. What this means for genealogical purposes is
that MtDNA identifies those people who are related through the mother's
mother's line back through time. However, whereas surnames for males can be
tracked back in time for perhaps 600 years or more and related to the passing
on of the male Y chromosome, societies tend not to preserve information on
maternal genealogy (unless there is a royal connection). Participants are
therefore most interested in the possibility of identifying others who have the
same genetic grouping or haplotype as they do, or, they are interested in
finding out about the origin of their particular haplogroup - for example where
did the woman who originated the genetic line live and how many tens of
thousands of years ago was she alive. Migration maps have been created to show how
migration based on mitochondrial DNA happened and also to show how the
different genetic lines developed. One such map can be found here:
http://www.transpacificproject.com/index.php/genetic-research/
There are three levels of testing: HVR (hyper variable
region) 1; HVR2; and FGS (Full Genome Sequence). Typically a participant will
match a number of others at HVR1 but matches will decrease the more detailed
the level of testing. Here is an example of report for haplogroup J1c1b1a:
Fig. 7 mitochondrial (MtDNA)
results
I should add that 23andme actually covers the whole genome X, Y and autosomal. It has a lot of medically relevant information as well although recent American legislation has limited the company's ability to offer this.
SNPs - Single Nucleotide Polymorphisms
Perhaps the most interest in DNA in the past year has been
generated by the developments in SNP identification. The following websites might help in the
understanding of the significance of SNPs:
https://www.genome.gov/Pages/Education/DNADay/TeachingTools/MakingSNPsMakeSense.html
https://www.youtube.com/watch?v=tJjXpiWKMyA
At the moment, as far as Scotland is concerned, the greatest
attention has been directed to using SNPs to distinguish the points at which
different clans split off from each other in the early Medieval period. Some of
the most important SNPs for this analysis were identified by Jim Wilson of
ScotlandsDNA using the Chromo2 chip. FamilyTreeDNA had previously released
their product - BigY -which was designed to test for a large number of SNPs but
did not include those which were of most significance to Scottish genealogy, though
they have since made the most interesting SNPsavailable for purchase as single
SNPs. Towards the end of this past year the company known as YSEQ started
offering panels (groups) of SNPs including those which identify the Scottish
clan groupings. The most comprehensive
genome testing is done by Full Genome Corp - which currently offers comprehensive
testing of the Y chromosome for less than 900 dollars US. This last is the only test currently
available (because it is comprehensive) which has the potential to identify
SNPs which are more recent and important for dividing up family groups in
historic time - that is, since the beginning of surnames. With this comprehensive Y test comes the
possibility of identifying all the SNPs which link specific families together
in the centuries since the introduction of surnames.
The most informative website for seeing what has been
learned so far about the relationship of clans is the one created by Alex
Williamson:
http://www.littlescottishcluster.com/RL21/NGS/Tree.html and
http://www.littlescottishcluster.com/RL21/NGS/R-L1335.html
which is the main group for those of Scottish descent of which the
MacGregors are part.
A summary version of the tree is found here:
The key discovery as far as Scots from
the Western Highlands is concerned came about through the work of Dr Jim Wilson
of Edinburgh University. Through his work using the Chromo2 chip the sequence
of SNPs ending with S690 which defined the MacGregor line was identified. Since
we believe that S690 was probably found for the first time in Gregor the
founder of the clan (who flourished c1360), anyone who thinks they might be a
MacGregor can test for this SNP on its own, and this is now much the cheapest
starting point in searching for genetic origins (but of most value to those who
believe that they currently bear an alias).
As far as MacGregors are concerned, there are intriguing suggestions
that a much smaller and less productive group of MacGregors broke off earlier than
1360, and it is speculated that those MacGregors and the McFarlands (now known
as 'hidden MacGregors') who have S691 or S695 are part of this group.
Current thinking is that SNPs occur
about every 90 years, and even if this is an underestimate it is clear that all
Scottish clans are very strongly related. The next Figure shows an adapted
version of the genetic tree identified by Jim Wilson (as presented to the
International Clan Gregor Gathering in summer 2014).
Fig.
8: SNP tree as presented by Jim Wilson in July 2014
The sequence of SNPs which arose is
therefore, in chronological order:
L1335
L1065
S749
S744
S691
S695
S690
MacGregor (and ?S697)
S696
MacGregor of Glencarnaig (Chief's line) (and ?S698)
According to the current date estimates
L1335 could have arisen at c790AD. We
believe that there are some, as yet undiscovered, SNPs between S690 and S696
(and S698) which define the Chief of MacGregor's line only. If S696 happened in
say 1420 we would expect to see more clan members having this SNP than appears
to be the case. At any rate it seems
likely that S696 dates to within the last 250 years. However do not currently
know the status of the SNPs S697 and S698 which seem to be related to S690 and
S696 is some way.
Thanks to the work of Dr Neil McGregor in
Australia we are beginning to break down the SNP results to see which
particular SNPs define which families. Our aim is to raise money through the
Clan Gregor Society in order to pay for full Y chromosome testing on 5
individuals who represent different branches of Clan Gregor. The difficulty
then will be in identifying the significant SNPs from the tens of thousands
which will be reported! The picture below taken from a recent Excel file shows
the speculative tree to date.
Fig.
9: Hypothetical breakdown of MacGregor genetic tree (as at December 2014)
This draft tree is based on the following data which Neil McGregor has derived from a combination of STR (marker) results and SNP results. The number on the left hand side is the Family Tree DNA kit number.
Fig.10 STR data on which Fig. 9 is based
Fig.10 STR data on which Fig. 9 is based
As usual if any individuals wish to see
how their results relate to anyone else in the project I am happy to do a
comparative chart such as those found on previous blog updates. Since this opportunity has been available to
all since the beginning of the project this offer is particularly directed to
those who have tested their Y chromosome in 2014. As usual my email address is
richardmcgregor1ATyahoo.co.uk (substituting @ for AT).
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