DNA Testing

      Just how good is DNA in determining relationship to a group, family, or individual? DNA tests are quickly gaining in popularity as a tool used by genealogists to help corroborate or expand their family tree. Increased test options and a wider variety of testing companies offer many options, but also confusion for genealogists . Which DNA test will best help you answer the questions you have about your ancestry?

      DNA tests are offered by a wide variety of testing companies, and each works a little differently. Most tests are sent with a cheek swab or small brush which you rub on the inside of your cheek, and then send back to the company in the provided sample container. Other companies may have you spit directly into a tube, or provide a special mouthwash that you swish and spit. Regardless of the collection method, however, what's important for the genealogist is which part of your DNA is being examined. DNA tests can help you learn about your paternal and maternal ancestry. There are also tests that can help you determine whether you are of African, Asian, European or Native American descent. Some of the newer genetic tests can also provide some insight into possible inherited traits and disease risk.

      Y-DNA tests specific markers on the Y-Chromosome of your DNA known as Short Tandem Repeat, or STR markers. Because females do not carry the Y-chromosome, the Y-DNA test can only be used by males. It passes down directly from father to son. Y-DNA also gives you your Haplotype to verify whether two individuals are descendants from the same distant paternal ancestor.

      Mitochondrial DNA (mtDNA) is contained in the cytoplasm of the cell, rather than the nucleus, and is only passed by a mother to both male and female offspring without any mixing. This means that your mtDNA is the same as your mother's mtDNA, which is the same as her mother's mtDNA, and so on. mtDNA changes very slowly so it cannot be used to determine close relationships as well as it can determine general relatedness. If two people have an exact match in their mtDNA, then there is a very good chance they share a common maternal ancestor, but it can often be hard to determine if this is a recent ancestor or one who lived hundreds or even thousands of years ago. You can also use an mtDNA test to learn more about your ethnic ancestry, or to trace your maternal lineage to one of the Seven Daughters of Eve, prehistoric women who shared a common maternal ancestor named Mitochondrial Eve.

      Autosomal DNA (atDNA) tests look at genetic markers found in the 22 chromosome pairs which contain randomly mixed DNA from both parents, basically all chromosomes except the sex chromosome, although some testing companies are now also providing data from the X chromosome as part of this test as well. Autosomal DNA contains almost the entire genome, or blueprint, for the human body; where we find the genes that determine our physical characteristics, from hair color to disease susceptibility. Because autosomal DNA is inherited by both men and women from both parents and all four grandparents, it can be used to test for relationships in all family lines. As a genealogy application, autosomal testing was originally introduced as a tool for determining biogeographical origins, or the percentage of various population groups (African, European, etc.) that exist in your DNA. Labs are now, however, offering extended family autosomal testing, which can help verify biological relationships through the grandparent generation, and potentially point to ancestral matches back as far as five or six generations, and sometimes beyond.

Which DNA test is best for you?

      Y-DNA (Y-Chromosome) If you are male and trying to confirm a paper trail researched by you or a family member then Y-DNA will help you confirm male lineage in a family. The level of matches will determine how far back in your family the levels that are compared (depending for which you pay) are normally 12 level, 25 level, 37 level, and 65 level. It is very unusual to have a 100% match unless it is your immediate family (less than 2 generations). A 12 level match says that you and another male could be related closely or as far back as 10 or more generations so if you don't have a confirmed paper trail it can be very hit or miss. Matching at 37 or 65 would give you a relationship with in a few generations. Normally you would use Y-DNA to confirm what you already know.

      mt-DNA (Mitochondrial) is used in just the female lineage but due to name changes of the females when married makes tracing or following the female lineage very difficult. It is very much like the Y-DNA and used in the same manner but for the female lineage.

      at-DNA (Autosomal) is used to confirm a common ancestor in two family lineages. This can be a male or female ancestor regardless of the name. It is usually with in just a few generations (3 - 5 generations) It can be farther in the past but becomes less reliable the farther you go into your family lineage. When there are to families with research and two members take a at-DNA it may indicate that an individual in the one family lineage is the same individual in the other family lineage. This seems to me as being the more desired means of comparing relationships between two family lineages .

      I used the Y-DNA the first time and had no positive results. I entered my cousin (since it is in my mother's lineage) for the Stiles family and have had no match what so ever even though there are over 165 Stiles family members in the group. This does not prove that he is not related to others in the Stiles family but there is some break some where for which we have not found yet.

      I also had a Y-DNA myself for the Wilt family. From this I had a positive result. I matched a Michael Wilt who lives in OH. We matched (6 generations) my great-great-great-great-great-grandfather). Henry Wilt b. 1740 d. 1780 is also his (7 generations) great-great-great-great-great-grandfather. I had confirmed proof that Henry is in my lineage but Michael did not have confirmed proof of his ancestor being the son of my Henry. The confusion was his ancestor's name was the same name as his father and he had left VA/MD for OH at a young age and did not have contact with his family he left behind. Henry also may have been from a previous marriage from which I am descended. Since we are tracing the Y-DNA it makes no difference

      I also submitted a at-DNA via Family Tree DNA and made a common connection with Ronald McDowell through his great-great-grandmother, Louisa Stiles Tuttle, the sister of my great-great-grandfather, John Stiles.

      I feel that the mt-DNA (Autosomal DNA) appears to be of more use to Genealogical research to make connections within a few generations. If we go far enough into the past we will find that we are all related. To me, DNA testing disproves more than it proves which explodes a lot of bubbles that people try to create that they are related to someone that is famous. Make up your own mind. This is just to give you some information of how I have used DNA testing in my research.


This is the results of atDNA test between myself and a cousin



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