DNA Testing: What Lies Beneath Our Skin?

A child’s genome is a mixture of the genetic materials from both parents. Only two things are untainted by the DNA of a mate: the mitochondrial DNA (passed from mother to offspring) and the Y-chromosome (passed from father to son).

There are times when mutations arise in DNA, thus creating unique sequences of A’s and T’s and C’s and G’s. These mutations, in turn, serve as genealogical markers that provide linkage back in time, to your maternal and paternal ancestors, and to all the places they have been.

So how do you get your DNA?

Scrape the inside of your cheek for several times. For at least $ 100, a testing company can put your cheek cells under a microscope. After few treatments on your cells, they can translate your DNA into your own genetic sequence known as a haplotype. A haplotype can tell you the major branch or haplogroup to where you came from.

Below are a few highlights about DNA testing. Here are common questions about this topic in genealogy. Answers are provided afterwards:

• When did DNA testing begin? During the year 1990, there had been controversial cases in which DNA was used to disprove or prove linkages of Thomas Jefferson, Sally Hemmings, and even the last Czar of Russia’s family to the deceased people. The events were highly publicized and the hype was escalated by media coverage until such time that DNA testing became commercially available in the year 2000.
• How does DNA testing work? Geneticists identify small areas in the mitochondrial DNA and Y- chromosome where DNA materials are untainted and are rarely affected by mutations. These materials are passed on to generations after generations.

Geneticists identify these keys to linkages.

• What does a DNA test reveal? A DNA test will show you a list of possible matches in a database. There are companies that can provide you with your ethnic origins. The initial 12-markers are hailed as “deep roots” markers and these may link you to other people of different surnames.

Moreover, these matches or links can tell you that you have a common ancestor before you actually had surnames.

• What if there are no matches in a database? Matches will soon be revealed as many people discover and realize the importance of DNA testing.
• Does the Y-chromosome recombine with the X? The Y does recombine with the X at the tip. However, the Y-chromosome used for DNA testing is the non recombinant part.
• Is it necessary to exhume an ancestor to get his DNA? The Y-chromosome is passed down to the males of the generation. So a close match with another male may lead to identifying a common ancestor.
•  If a genealogic “brick-wall” is present, how is an ancestor identified? A common ancestor can easily be revealed as long as there are enough matches available in a database. If a paper trail genealogy is available, a brick wall is only a simple problem.
• Which test must I take? If you want to obtain the closest match available, begin with the test that can reveal more markers. You may take other tests and upgrade later if your finances can not support at least a $100.
• Is DNA testing a blood test? No. most DNA testing companies use swabs that will be scraped inside your mouth. There are other companies that uses chewing gums while another uses a special mouthwash.
• Does blood transfusion alter one’s DNA? The answer is no. However, there are companies that ask clients to have the test conducted after a month.
•  Does radiation or chemotherapy affect DNA results? It is recommended that DNA testing be conducted after a few months after radiation or chemotherapy treatments are done. However, these treatments do not seem to alter or affect DNA results.
• Can one’s DNA sample be used to clone him or her? The answer is simple. No.
• Can a DNA sample be preserved for future options? Yes, there are companies that offer long-term storage of DNA samples. Another one is the so-called DNA Banking/Archiving where DNA samples are stored with directives.

Paradoxically, the more we think that every race is different, the more samples after samples reveal the connections behind all these differences. You may agree, then, that you can be a metaphor of a whole country as geneticists are able to test what lies beneath your skin.