Have you heard about the latest tool available for tracing your genealogy? I’m referring to DNA testing. We’ve all heard of DNA, it is that genetic code that every person has built into your body at the cellular level. In the past DNA testing was a very expensive process but recently the prices have come down considerably and several companies have appeared that specialize in DNA testing for genealogical purposes. These tests are very simple and painless.

How can it help with genealogy? There are several different types of tests. I’ll go over them one by one with the simplest explanations I can manage. These explanations will be overly simplified so won’t contain a lot of confusing scientific jargon.

Y-Chromosome Test - For Males only, paternal ancestry (surname study)

mtDNA Test - For Females only, maternal ancestry

DNAPrint Test - What major population groups make up the bulk of your recent ancestry?

For More Information

Y-Chromosome Test used for Surname studies

The "Y" Chromosome is something that is genetically handed down from father to son, so only males have a Y-Chromosome. While many aspects of DNA are unique to each individual, the Y-Chromosome does not change until many generations pass. That means, in theory, that your Y-Chromosome will be a perfect match with your fathers, your grandfathers, your great grandfathers, and so on back many generations. Since the Y-Chromosome goes from father to son, your great great great grandfather’s male descendants (in direct lineage) should all have an identical Y-Chromosome.

Consider the fictional family of John Jones and wife Margaret Smith. They had three children, two sons (James and John Jr) and a daughter (Mary). In the chart below I show a list of their direct descendants, assume that the last generation listed are people still living today.

John Jones and wife Margaret Smith
s: James Jones			s: John Jones Jr		d: Mary Jones m: Thomas Brown
gs: William Jones		gs: Thomas Jones		gs: John Brown
grgs: Samuel Jones		grgs: Zadock Jones		grgs: Emanuel Brown
grggs: David Jones		grggs: Richard Jones		grggs: Timothy Brown
grgggs: Martin Jones		grgggs: Frank Jones		grgggs: Andrew Brown

Martin Jones, Frank Jones and Andrew Brown are all 3rd Great Grandsons of John Jones. They are 4^th cousins to one another, John Jones being their common male ancestor.

If all three men took the Y-Chromosome DNA test, Martin Jones and Frank Jones should match each other exactly or almost exactly. Andrew Brown, however, would not match them at all, as his DNA would be that of his direct male ancestor Thomas Brown, and not of his Jones ancestry. Y-Chromosomes go from father to son. Andrew Brown wouldn’t have the same DNA as his Jones cousins since his Jones lineage has a female Jones in it, and females don’t have Y-Chromosomes. Suppose there is a Matthew Jones who takes the test also. His ancestry is unknown, but his results match those of Martin and Frank Jones. That means he is also from the same Jones line. He could be a descendant of old John Jones too, or his line could be connected further back, but he is certainly related. If George Jones takes the test, and his DNA doesn't match, then that means his is an unconnected Jones line and he is not related to your Jones.

If I take the Y-Chromosome test, my results ought to match all of my male Grant cousins. So if John Doe Grant, my 5^th cousin, 6 times removed, takes the test, his results should be identical to mine. If our results match, then that proves we have a common direct male Grant ancestor within a certain number of generations. If our results do not match, then one of us has either made a mistake in our genealogical research or we have a "non paternal event" in our lineage. That means that one of us may have a male Grant ancestor who was adopted and not a Grant by birth, or that he was born out of wedlock, meaning his father was not the Grant, but his mother was (remember, females don’t have the Y-Chromosome).

The value of this test goes way beyond confirming relationships you already know (for example you and your brothers should all match, you and your male 1^st cousins of your surname should match, etc.). The real value comes when someone’s results matches yours who’s connection to your family is not proven. If you share the same surname and have no non paternal events, then that normally means you do have a common direct male ancestor, even if your regular traditional research has not yet made the connection, genetically your relationship is proven. Now it is up to you to find the paper trail to tie it all together. It also helps when there is no match found, for then you know your line and the other persons are not related.

There are two test levels: The 12 marker test and the 25 marker test. The "markers" are genetic codes which I can’t explain so I won’t try, but they are numbers that you can compare to the other test participants. A "match" means your numbers and his are all the same. The 25 marker test is more extensive (and more expensive) so it is a better test to take.

If you take the 12 marker test and your cousin takes it, you have to have a 12/12 marker match to prove you share a common male direct ancestor. Anything less than a perfect match for this test means you do not have a common male direct ancestor. When you take the 25 marker test, you can match perfectly 25 for 25, or possibly be off one, matching 24 for 25 and still consider it a match.

The Y-Chromosome test is also called a Surname test because it is only useful for working with your paternal ancestry, in other words, only with your family name. In my case, being a Grant, it won’t help me with my mother’s family at all, nor the "other" branches of my dad’s family, except his direct Grant ancestry. That is because the Y-Chromosome only goes from father to son. Daughter’s do not inherit it, so it does not help with "branches" of the tree, only with the "trunk" to use the Family Tree analogy. Two people of different surnames can not compare their results as they most likely won’t match, and even if they do, it won’t mean they are related. These tests won’t confirm any old relationship, just those based on common direct male ancestor of the same surname. For example, I have male 1^st cousins on my mother’s side of the family. Our results would not match. I also have male 1^st cousins on my father’s side who are children of my dad’s sister. Their test results will not match either since it goes up their father’s genetic tree and not their mothers (who is my blood relative).

In my case I know that my test results will match all my 1^st and 2^nd male Grant cousins, but will not match my more distant Grant cousins. This is because my Great Grandfather Grant was born out of wedlock. His father was not a Grant. This ruins the test for me as my results will not match the other Grants out there, except those in my own immediate part of the family. However, it does not make the test useless, for I do know who my Great Grandfather Grant’s father was, or was alleged to be. His father was supposed to be a man named Patterson. Theoretically if I could get some of Mr. Patterson’s direct male descendants (or his brother’s descendants) to take this test I would match them perfectly, since as far as Y-Chromosomes go, I’m a Patterson. Legally I’m a Grant, and certainly my Grant ancestry goes all the way back, but not in a direct line due to the out of wedlock birth.

Qualifications:

Must be male and have a traceable paternal male lineage back at least a couple of generations. Females can participate indirectly by recruiting their fathers, brothers, or other close male relatives to participate.

If your ancestry is like this, you can take the test with good results to compare to others of your surname:

William Grant

. Andrew Grant

.. Thomas Grant

... John Grant

.... Carson Grant

..... You.

If there is a non paternal event, you can still take the test, but the results won’t be completely applicable to your surname, for example:

William Grant

. Andrew Grant

... Thomas Grant

.... John Grant

..... Hattie Grant, unmarried, had child out of wedlock

...... Marvin Grant.

....... you

You could take the test, but you won’t match all the other male Grant descendants of William Grant, you’ll only match those in your line after the non paternal event.

Now, the Y-Chromosome test is only for males and only for your direct male lineage, your father, his father and his father’s father, and so forth. Are women left out completely? No. Read on.

mtDNA test (Mitochondrial DNA) for your maternal ancestry.

The mtDNA test is similar to the Y-Chromosome test except that it is for females and traces your direct maternal ancestry. mtDNA is handed down from mother to daughter, so this test should show identical results for you (if female), your mother, your mother’s mother, and so forth, back many generations. This is not real useful for surname studies unless you work it out to compare your results with someone else who shares your maternal ancestor of interest and descends in the same geometric way you do (female to female to female, all the way to the present). For example, say you are Ms. Smith (your maiden name), your mother was a Ms. Jones (maiden name), her mother was Ms. Thompson, and her mother was Ms. Johnson. If you take the test, and another direct female descendant of Ms. Johnson takes the test, you two should have matching results. Non paternal events won’t skew these results for it goes female to female and in most cases the mother is the mother (unless there was an adoption).

DNAPrint test results show which major population groups your ancestry comes from.

This test is available for males and females. Your results will show you what major population groups make up the bulk of your ancestry over the past couple of hundred years. For example, my test might show these results:

Western European: 90%

Native American: 5%

African: 5%

There is a small percentage of error involved, and these tests are only good for a finite number of generations, so your results may not be what you expect.

For More Information

There are numerous places on the Internet that talk about DNA testing in various amounts of detail. Go to the source at FamilyTreeDNA.com and watch the video on this subject and get the current prices. Find out if a surname project is already in progress for your surname of interest.