McGrew DNA Project - 2006 Year End Report

12 and 25 Marker Results for Project Members (26-37 Marker Results for rows 5, 6, and 7 match exactly)

from www.familytreedna.com/public/mcgrew

Row   Kit #

1       67017 13 24 14 10 11 13 12 12 12 13 13 30 19 9 10 11 11 25 15 19 30 15 15 17 17
2       55457 13 24 14 10 11 15 12 12 12 14 14 30 19 9 10 11 11 25 15 19 29 15 15 17 17
3       64469 13 25 14 10 11 13 12 12 12 13 14 29
4       68562 13 25 14 11 11 13 12 12 12 13 14 29
5       61737 13 26 14 11 11 13 12 12 12 13 14 28 17 9 10 11 11 25 15 18 31 15 16 17 17
6       53756 13 26 14 11 11 13 12 12 12 13 14 29 17 9 10 11 11 25 14 18 31 15 16 17 17
7       52842 13 26 14 11 11 13 12 12 12 13 14 29 17 9 10 11 11 25 15 18 30 15 16 17 17
8       60818 13 26 14 11 11 13 12 12 12 13 14 29 17 9 10 11 11 25 15 18 31 15 16 17 17


When I began the McGrew DNA Project in February 2006, I had three goals in mind. The first was simply to see if it
was possible to establish a genetic ancestry for Robert McGrew. The second was to try to establish a genetic link
between Robert's northern McGrew's and the southern branches of the family. The third was to determine if
McGrew's are related to the McGregor Clan of Scotland as my family lore suggested or, if not, to establish what
Scots Clan we are related to.

Although we end the year having only eight Project members I believe we have accomplished a good portion of these
goals. When we found a 12/12 marker match (see comments on matches below) between kits 53756 (row 6) a
known descendant of Robert McGrew and kit 52842 (row 7, me), a probable descendant of Robert who can't
confirm one link, goal #1 was accomplished. It was very rewarding to have this occur with the first two sets of results
processed. Kit 61737 (row 5) with an 11/12 match with kit 53756 (row 6) and a 35/37 match with kit 52842 (row
7, me) is also likely to be a descendant of Robert.

Our second goal was also achieved when a 12/12 match was found between kit 53756 (6) and kit 60818 (8), a
known descendant of James A. McGrew, a southern McGrew. Kit 60818 (8) also had a 24/25 match with kit
52842 (7, me). Both James and Robert are believed to have immigrated to the Colonies from Omagh, N. Ireland. I
am calling these lines the "Omagh McGrew's".

In March, 2007, kit 53756 (row 6) upgraded from 12 markers to 37. We now have two 35/37 matches and one
24/25 match among the "Omagh McGrew's". This level of match remains indicative of a recent genetic relationship
among these individuals. Particularly interesting is the close match (24/25) between the known descendant of
Robert (row 6) and the descendant of James A. (row 8), a southern McGrew.

Our third goal has been partially achieved. I have examined a typical set of McGregor DNA results found on their
website and determined that there is no genetic relationship between McGregor's and McGrew's. I have also
examined over 1,000 DNA results from a Scottish Clans DNA database and found no consistent matches within a
clan with our results. Some clans of interest (Fraser, Buchanan and Drummond) have very few published samples,
and I continue to look for samples for comparison.

I would like to call your attention to several aspects of our family DNA results that I find very interesting. First our
heritage is Irish. We may be Scots, but we came to Scotland from Ireland. This fact became apparent as I compared
our DNA results with others using a geographic analysis. Our DNA is very close to that of about 20% of Northern
Ireland males. This result has caused me to do a lot of reading about the origins of the Scots. Many Scots in western
lowland Scotland came to Scotland from Ireland, and there was an Irish kingdom, Dal Riata, that encompassed
northern Ireland and western Scotland from about 500-900 A. D. Also the Roman word for the Irish was Scoti.
Other immigrants to Scotland were the Picts, Angles, Norse and Jutes each with distinct DNA types. We are Irish.

Genetic genealogist David Wilson has proposed an R1b1c7 haplotype that is common in western Scotland and
northern Ireland (see www.m222.net/R1b1c7). Six of our results (rows 3-8) match this type. This even more firmly
establishes us as being Irish before we were Scottish. Wilson wonders if we were among the earliest immigrants to
Ireland possibly as far back as 8,000 B. C. I have included several suggested readings that discuss the origins of the
British peoples.

I have discussed the genealogy and genetic relationships of four of our Project members. Kits 65862 (4) and kit
66469 (3) are also interesting. They have an 11/12 marker match. This level of match suggests a possible genetic
relationship (see below). Kit 66469 has not provided any known McGrew ancestors. Kit 65862 can trace his line
back to William Van Buren McGrew born in KY about 1843. Because of the possible relationship between these
two individuals I looked for a common ancestor. I believe I found the ancestor in the McGrew database. Particularly
interesting is the possibility that this ancestor (John H. McGrew) is descended from Thomas McGrew who may be a
brother or cousin of John Flood McGrew, a noted southern McGrew. If so we have another southern line that shows
a possible genetic relationship to other northern and southern lines. We would need at least a 25 marker result set to
more firmly establish the relationship between these individuals, and the existence of a genetic relationship with the
Omagh McGrew's.

Kit 55457(2) shows no genetic relationship to any other Project members. The most distant ancestor reported is
Alexander MacGruar who was born in Scotland in 1706 and immigrated to the Georgia/South Carolina area about
1735. MacGruar apparently immigrated directly from Scotland unlike Robert and James McGrew who were
Scots-Irish and immigrated from Omagh, N. Ireland. I have been unable to match these DNA values with any
geographic location.

Kit 60717 which had traced its ancestry to Robert McGrew has a broken genetic link in its male line.

I have had some questions from our Project members and others interested in our results about the number of matches
required to suggest a genetic relationship between individuals. Differences in marker values between a father and son
are the result of a mutation during the copying of the son's Y-DNA (transcription). There is an average error rate of
0.2-0.4% in the transcription process for each marker. The variation in error rates depends on both the identity of the
marker and the individual doing the copying. Different markers have different mutation rates and different individuals
(probably family lines since the transcription process is also inherited in the gene) have different mutation rates. If we
initially assume a 0.2% error rate per marker copied and continue the process over 10 generations (the approximate
genetic distance between us and Robert McGrew) we get a 2% error rate per marker. For 25 markers over 10
generations the total error rate would be about 40%. Thus for a 25 marker test 2 individuals separated by 10
generations from Robert McGrew should expect slightly less than a 1/2 chance that one marker has mutated. For a
0.4% rate the chance would be about 2/3. Thus we would expect at worst a 24/25 match. For 12 markers we
would expect 12/12 with 11/12 suggesting a possible match particularly if the marker in question had a higher than
average mutation rate (colored in red on the Family Tree chart).

Where do we go in 2007? We need more Project members. My biggest surprise as director has been the reluctance
of McGrew's to join. We need a known descendant of Thomas McGrew. I am in touch with a descendant through
his maternal side, and I hope he can convince one of his cousins to join. We need a descendant of John Flood
McGrew to join. I have contacted several but, so far, to no avail. I would also like to have a descendant of Robert
through other than his son James. I am also trying to get a sample from William McGrew of Omagh or one of his
relatives. His family is thought to be related to Robert through a brother or cousin who stayed in N. Ireland. As the
year progresses please check the Project website occasionally, and I will send out emails if a particularly interesting
result occurs.

Suggested readings:

Oppenheimer, Stephen," The Origins of the British", Carroll & Graf Publishers, 2006.
Sykes, Bryan, "Saxons, Vikings, and Celts", W. W. Norton, 2006.
Smolenyak, Megan and Turner, Ann, "Trace Your Roots with DNA", Rodale, 2004.