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The question is “Can I help Sheffield Surname Genealogy by taking the Y-DNA test?” If you are or know a male with the Sheffield surname, the answer is probably YES.
So far, Y-DNA testing has revealed two major groups. The well known families of Sheffields from the 1700’s in North Carolina counties Northampton, Moore and Duplin form one group. I call these families “Group I” from their genetic Haplogroup, I1. The other major group seems to originate with Virginia families, but really they should be thought of as all of the English Sheffield families NOT in Group I. This second group I call “Group R” from their genetic Haplogroup, R1b1b2. Group R is the most frequent in Western Europe and is known as the Atlantic Modal Haplogroup, AMH.
Two minor groups were also found. One was for a family from Germany whose name was anglicized to Sheffiel. The other is of unknown origin, perhaps they are immigrants from Ireland (just a guess).
In the current market, Y-DNA tests come in three sizes. The basic test covers 12 segments of junk DNA from the Y chromosome. The mid-range test covers 37 segments and the deluxe test covers 67 segments.
When the first Sheffield DNA project was started it was soon discovered that the Northampton/Duplin/Moore families were in Group I. That project quickly built up a collection of matching results from mostly Y-12 tests. There were a few Y-37 results also. In all but one result, the first 12 segments were all alike for the Group I members. Currently there are over twenty results with perfect matching Y-12 Group I DNA.
While the Y-12 test is good for placing one in either of the Groups, It takes the more refined Y-37 test to establish a close relationship when the match is not perfect. When all results are the same for a Y-12 test, then a more extensive test with more markers is needed for separating lines from one another. For Group I, the Y-12 test will likely not reveal the line you are from. Of six Y-37 results, 2 have DNA changes. Using the Y-37 test will better expose what changes have occurred in each line.
The first Sheffield project also collected a few Group R results, but none of them had perfect 12 segment matches.
I will tell you that the two groups share no common ancestors in any genealogical significant time. These two groups developed in different parts of Europe at different times in the past. The most recent time they could have merged, scientists believe, was around the time of the Last Glacial Maximum in Europe, 12,000 years or more ago.
It is not true that only perfect matches are important to genealogy. Depending on the test used, a 1-off match for a Y-12 test to 4-off for a Y-37 test, the results can predict a family connection between two people over 8-12 generations.
A mutation is the event of an error in copying the DNA that a parent gives a child. This mutation, or change in the DNA pattern of junk DNA, then becomes the DNA of the child and passes to the descendents of the child. By recognizing and documenting the different patterns of these junk DNA segments, a genetic genealogist can predict which family lines support a living person’s y-DNA result. It also can eliminate some lines from a possible connection.
The DNA of ancestors is predicted from the DNA of two descendents. If the two don’t match then a third descendent is needed to break the difference. When a change is found, initially it is not known when the change happened. It could be at any generation between the living person and the most ancient paternal ancestor.
For Y-37 testing to be worthwhile, two people first must have a reasonable closeness from their Y-DNA. For some of the Group R lines, this closeness does not exist yet. For a few it does. I can recommend when I think Y-37 testing is worthwhile for those people.
To summarize, I feel all potential Group I members should order only Y-37 tests. If you are in Group R or if you don’t know where you are going to fit, then a Y-12 test would be less expensive to begin with. Later you can decide whether to upgrade or not. Be aware however that an initial Y-37 test costs less than doing the Y-12 test and then an upgrade.
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