Y-DNA is the male chromosome that is passed from father to son down through the centuries, most often with no “corruption” or deviation whatsoever. Only males pass on the Y-Chromosome of the father, his father’s father, and his father, etc., etc. In other words, the patrilineal lineage in your family tree. Y-DNA can tell you (or your brother, uncle, or male cousin by the same grandparents) from where in the world your male ancestor originated.
Y-DNA tests differ from Mitochondrial DNA (mtDNA) in which the mitochondria is passed from a mother to her children. This test can also trace back hundreds of generations/years to a common female ancestor. In other words, my mtDNA can be traced back to my mother’s grandmother to her mother, to her mother, to her mother, etc., etc. Males can take this test as well but the ancestor tracing will only reveal the matrilineal lineage in the family tree.
atDNA, or autosomal DNA, is a DNA test that males and females can take. The AncestryDNA test is an autosomal DNA test that I, several siblings, and various cousins have taken. It has the ability to show you whether a given relative is a sibling, parent, aunt, uncle, or cousin and distinguish whether that relative is male or female (brother/sister, mother/father, aunt/uncle – you get the picture). If everyone in your family takes the AncestryDNA test, it can tell you whether you’re siblings, half-siblings, and the degree of cousinhood you likely share, i.e. First, Second, Third, etc., including the “removed” scale.
Three of my male cousins in the McGrew family took the Y-DNA test. The results show these gentlemen all share the same common ancestor, i.e. their Y-DNA is an exact match. They all have Y-DNA matches with the surname McGraw and McGrew that are 3 steps from sharing the same common ancestor as my cousins (there are other surnames as well but these are due my immediate attention*).
For example: All three of my cousins who took the Y-DNA test are all descended from Martin McGraw, Sr. through his younger son, Thomas McGrew. But one of their Y-DNA matches – let’s call him “G_ McGraw” for privacy’s sake – is 3 steps from the same common ancestor as my cousins. I traced G_ McGraw’s ancestors and he is descended from Samuel McGraw, another son of Martin McGraw, Sr. The further from the common ancestor, the more “steps” the Y-DNA algorithm assigns to the match. But I’ve determined that G_ McGraw is indeed a distant relative with Martin McGraw Sr as the ancestor he shares in common with my McGrew cousins and I.
The same holds true for many of the other McGraw’s who submitted their Y-DNA to FamilyTreeDNA.com: Each is descended from one of the sons of Martin McGraw, Sr.
Except one: I’ll call him “MJ McGraw.” MJ McGraw is also 3 steps from the same common ancestor as the males referenced above. BUT MJ McGraw’s ancestors didn’t come to West Virginia in the early 1790’s like mine did; in fact, MJ’s ancestors pretty much inhabited Bedford County, Pennsylvania up to the 1990’s. I know this because I worked MJ McGraw’s tree back to his X-great grandfather, Edward M. McGraw born 1817.
This got my heart thumping. This likely means that Edward M. McGraw’s father – whoever he might have been – may very well have been a brother, perhaps a nephew, of my ancestor Martin McGraw, Sr. In those days, if you had two men by the same surname in a given vicinity (tax list, census locale/township) you may very well share a familial relationship. There are exceptions to that: Smith, Jones, Martin, and common surnames along those lines are NOT always related). But in the case of McGrew or McGraw, uncommon surnames at the time, you might want to hold your breath.
So, my conclusion is that Martin McGraw of Bedford County, Pennsylvania in 1779 through 1788 is most likely my ancestor Martin McGraw whom I’ve been trying to pinpoint for a number of years. Please understand that there are several PA counties containing records for “Martin McGraw” in the Land Warrants and the tax lists: Philadelphia, Northumberland, and Westmoreland, to name a few, all in the same time frame.
I can’t expect you, gentle reader, to be as excited as me. But I am absolutely “tore out of the frame.”
*The McGREW Y-DNA Matches are descendants of John Lewis McGrew, grandson of Thomas McGrew, who died 1889 in either Protem, Taney, MO or Boone County, Arkansas.