This article was written by
John David Grierson, known in the family as John
(6), the 5th generation descendant of John
Grierson who was born 1778 at Parton, Scotland,
and who died in Australia in 1855. It includes
material dating from 2005. It is a work in
progress, and may be amended as the research
progresses.
During 2002 I became interested in DNA testing
(particularly YDNA) as an aid to conventional
genealogy. The interest arose from the
"brick wall" that seemed to have arisen
in the search for Grierson ancestors, when it
became apparent that the limit to easily
accessible documentation had been reached. By
2003 I was well into the testing regime, and in a
position to begin to draw conclusions from the
study, albeit those conclusions were somewhat
tentative because it was also apparent that the
science was evolving rapidly, as it continues to
do. Those early conclusions can now be seen to
lack definition by comparison with more recent
results, and doubtless there will be future
advances that clarify things further. YDNA is
that portion of the DNA transmitted only by a
male at the time of conception. These notes are
mainly directed at YDNA analysis, but much of the
terminology is also applicable to mitochondrial
DNA passed down by the female line.
At that time, analysis of Short Tandem Repeat
(STR) strings was the available system to
determine relationships. An STR is a
microsatellite on the human genome which may
repeat numbers of times, and these repeats can be
different in different men. However, during the
recent 18 years of development of the science as
applied to genealogy, particularly in the hands
of enthusiastic amateurs, we have seen that a
better way to define male ancestry (that is, the
YDNA trail) is to establish the youngest Single
Nucleotide Polymorphism (SNP) carried in the
YDNA. An SNP is a specific combination of
proteins at a particular position on the human
genome. One issue has been the greater
expense of testing for SNPs over that for testing
STRs, but advances in technology have made SNP
testing more affordable. [The reader is advised
to explore the meanings of STR, SNP and
microsatellite in Wikipedia.]
For clarity, we now need to look at some
more technical detail. A haplogroup defines a
body of men who carry the same SNP mutation.
During the period, as it became possible to test
for haplogroups (as distinct from estimating
them) we began to see more clustering of men,
both within a surname group, and in the broader
community. SNP mutations are very rare, and we
presume that once they have happened, they are
never reversed, certainly within the recent tens
of thousands of years. So when a mutation has
occurred during the conception of a male, it is
assumed that all his descendant males will
exactly match his SNP haplogroup or if there has
been a further mutation, one of its sub-clades -
he is the father of a tribe, so to speak.
The classification of haplogroups has
developed with the increase in knowledge. By
international agreement, the principle divisions
are labelled with a letter of the alphabet
roughly corresponding to the age of the
subdivision, so we see haplogroup A as
representing those whose ancestry has changed
little over the thousands of years of humanity.
It is rare because many in the line died out
without issue, and many mutations have occurred
in the thousands, if not millions of years
involved. For our purposes we should note that
haplogroups I (probably mostly seen in those with
northern European ancestry) and R (mostly seen in
those with western European ancestry) are the
major haplogroups of interest. The next step was
to divide a haplogroup into clades,
so when different mutations within R appeared
they became R1 and R2. The next change would be
reflected by R1a and R1b, and so on. For a number
of years, the International Society of Genetic
Genealogy (ISOGG) standardised a nomenclature
which used alternate numbers and letters to
identify SNPs, for example, R1b1c7 being a
sequence that described a younger SNP underneath
R1, and early on was the code for the R-M222 SNP.
The problem that then arose was that, with
the rapid advance in the testing, many younger
SNPs were being identified, and descriptions such
as R1b1b2a1a2f2 (which R1b1c7 had become in two
years) were becoming cumbersome, so many (and now
most) genealogists changed their practice to that
of identifying SNPs by their commercial title,
that is the name given by the company that first
identified them. So we see FGCxxxx (being an SNP
discovered by Full Genomes Corporation), or
BYxxxx, one discovered by Family Tree during
their Big Y program. There are
possibly ten companies testing, so there are
quite a range of prefixes to be seen.
The terms clade and haplogroup
are often used interchangeably we find now. From
my point of view, the haplogroup that matters is
the youngest SNP identified in more than one man,
but we also need to know where that SNP sprang
from.
THE DEEPER ANCESTRY
The name Grierson (the modern spelling) is a
South West Scottish surname, first noticed in
extant documentation (as Greresoun and Greresone)
in the early years of the 15th Century (ie, son
of Grere as distinct from Gregor, although that
might be a function of Gaelic pronunciation) . It
appears in a charter relating to the sale of land
in the Nith valley in the area then known as
Galloway (being the Stewartry of Kirkcudbright,
Wigtownshire, and parts of modern Dumfriesshire
and Ayrshire). This deed addressed the change of
ownership of an estate known as "Lag",
and described the sale of the property by John
McRath of Laught to Gilbert Grierson of Arde. The
Griersons of Arde appear to have been hereditary
bailies of the barony of Tibbers in the
fourteenth century and by the end of the century,
they were armigers. The sale was confirmed by
Henry, Earl of Orkney, Lord of the valley of Nith
on December 6, 1408. Lag was clearly a superior
estate to Arde, and so Gilbert and his heritors
have maintained the appellation "of
Lag" since then. A seal affixed to a 1418
document states "Gilbert, son of
Duncan". (There is reason to believe that
this Duncan is the one mentioned in the mid-14th
Century in Galloway.) George Dunbar, Earl of
Dunbar and March was Gilberts feudal
superior at the time of the purchase of Lag.
During the next four hundred years, the family
prospered, and ultimately became owners or, in
the case of some cadet branches, kindly tenants,
over very large tracts of land in the south of
Scotland. In 1685 the Laird of Lag was made
Baronet. By the 18th Century the name had spread
widely throughout Galloway and Dumfriesshire.
At various times, but principally in the 16th and
17th Centuries, the name Grier was used as a form
of shorthand. There are numerous documents and
legal reports of the era in which the same man is
referred to by both Grierson and Grier. In a
descent chart (the Carrickfergus tree) produced
under the sponsorship of Thomas Greer of Sea
Park, Carrickfergus, Ireland, a High Sheriff and
Member of Parliament in the latter part of the
19th Century, during the early 17th Century a
branch descending from a brother of the then
Laird of Lag is said to have migrated to Ireland,
at the same time changing the preferred spelling
from Grier to Greer. Oral tradition has it that
another son of that branch migrated to North
America at or about the same time, and his
presumed descendants also use Greer. Later, some
of the Irish Greers also emigrated, to North
America. Greer appears only rarely in Scottish
records.
There are family legends and clan
legends, and there is also deliberate
misinformation about Grierson origins. Were we
MacGregors? Are we Irish? How do we take the next
step in identifying our forefathers? The answer
may well be in recent advances in the study of
DNA, as passed from father to son.
The link below is to The DNA Journey which
describes the process by which I arrived at my
conclusions. Appendix 1 is a demonstration of how
a specific combination of STRs gave David Wilson
the idea that a new SNP might exist, and also of
how a modal exists. Appendix 2 shows how I
extended Wilsons idea leading to the
identification to several new SNPs, and how STR
analysis can be used to identify families.
This has been updated 8 August 2020. |
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