McCaffrey DNA Project Discussion
We are fortunate to have achieved some early success with the McCaffrey DNA
Project. To date, we have the yDNA profiles for twenty-two members and the short
lineages for fourteen. In our experience, this is a better than average start
for a yDNA project.
We have already achieved one of our initial goals. We wanted to prove that some
modern day variations of the McCaffrey name are related. Specifically, we have
proof that a McCaffrey, a McCaffree, a McCafferty and a Caffrey have a Common
Ancestor (CA). These facts should serve as a wake-up call to those who
overemphasize the importance of surname spellings in their research efforts. It
should also encourage those with variant spellings to join the project.
However, we have encountered an impediment to our progress. Apparently, in the
early days of yDNA testing at FTDNA, Several McCaffrey, etc. men had their yDNA
tested; however, because a McCaffrey DNA project did not exist and they probably
did not get many or any matches, they seemed to have lost interest. This
situation has resulted in three important FTDNA yDNA matches, however, we only
know a few details about these people. We have tried to email two of these these
folks, but these attempts have been unsuccessful; some bounced and some have
gone unanswered, indicating that these addresses are probably not being used for
some reason. Privacy policies at FTDNA do not allow them to provide any other
information. We need these people to join our project or contact us. This action
could lead to significant lineage connections and lineage extensions.
Therefore, we are going to list what we know about these mystery folks in hopes
that a reader will recognize a name and assist us in some way.
John Edward McCaffrey, kkennedy@---.com
GD= 2 w/ kit # 486944
James McCaffrey maggiemae1201@----.com GD=3 w/ kit # 319977
? McCafferty, no email, Most distant ancestor is Hugh McCafferty GD=1 w/ kit #
346400 & GD=2 w/ kit # 250346
The Genetic Distance (GD) between two
yDNA profiles is the number of marker (DYS#) differences found when the two
profiles are compared. In general, for 37 marker profiles of the same/similar
surnames, a GD of 0 to 5 is considered a match and for 67 markers, a GD of 0 to
7 is considered a match; however, these conventions are based on the observed
average mutation frequencies of all surnames. There are a small number of
surnames that fall on both sides of this average, sometimes significantly so.
That is, some surnames have mutation rates well above that average and some have
rates well below the average; therefore, the GDs of the these exceptions may
have different interpretations than those for the general population (average).
For the general population, smaller GDs usually indicate closer relationships;
however, as demonstrated by Group 3, this is not always so. Group 3 includes at
least three individuals with GDs=0/1 that are at least 5th cousins and are
descendants of a McCaffrey born at lesast 250 years ago. This is a small sample,
but implies a mutation rate of approximately one per two hundred fifty years and
when extrapolated, four per one thousand years.
Our project success and some of our
participants yDNA genetic profiles have encouraged us to do some additional
historical research. First, it is helpful to know that when the genetic profiles
of individuals with completely different surnames are compared, small GDs
indicate the possibility of a Common Ancestor (CA). The smaller the GD, the
greater the probability of such a connection. In addition to comparable GDs, the
number of matches with comparable GDs is at least as important. That is, a large
number of matches with comparable GDs with a dissimilar surname increases thes
probability of a genetic connection between the two dissimilar surnames. Group
3 members of the project have over thirty matches with individuals surnamed
Maguire/Mcguire, some as close as GD=2@67 markers. Also, Group 4 members have
about the same number of matches with individuals surnamed Doherty/O'Doherty and
variations, some as close as GD=1@37 markers. Some insight into this phenomenon
comes from Rev. Patrick Woulke in his 1923 reference, Irish
Names and Surnames. The Rev. Woulfe divides the surname origins into two
"tribes". The first and most widely known was derived from Gadfraidh, the son of
Donn Mor Maguire (1260 AD - 1302 AD). Over the years this name became Mac
Gadfraidh, M'Gafferie, MacGaffrey,
MacCaffray, MacCaffrey, MacCaffery, Caffrey, etc. Bearers
of this surname were part of a
sept (sub clan, division) of Clan Maguire which ruled the Fermanagh region from
about 1250 AD to 1607 AD. The second tribe was derived from Eachmharcach
(horse rider), a given name often used by the O'Doherty Clan of Counties Donegal
and Mayo. This name evolved into MacEachmharcaigh, M'Cafferchie, M'Cafferkie,
MacCaffarky, MacCagherty, MacCaugherty, MacCafferty, MacCaverty, MacCaharty,
MacCaherty, MacCarthy, MacCaffry, Cafferky, Cafferty, etc. Irish history
provides abundant evidence of the Maguire/McCaffrey connection in Fermanagh. In
fact, the McCaffrey, etc seat of power was established at this time in the small
townland of Ballymacaffry in Fermanagh. Ballymacaffry still exists and is near
the border of County Tyrone, just west of Fivemiletown and about 13 miles due
east of the much larger town of Enniskillen. Enniskillen is the location of the
Maguire Castle, a well known tourist destination constructed in the 1420s. The
ancestors of both the Maguires and O'Dohertys have been recorded by Irish
historians well before the end of the first millennium. This research has led us
to another interesting fact: In the earliest Irish records, related families
used the MacCaffrey, McCaffrey, McCaffery, McCafferty, Caffrey and similar
variations. Since Caffrey was a McCaffrey variation used in Ireland, it surely
existed in other places. so we have added Caffrey, etc to our list of potential
project participants.
Created Jun 7, 2016
Revised Jun 11, 2018