Genetic Genealogy

The root word of genetics, “gen,” literally translates to mean “birth” or “produce.” Consequently, genetic genealogy, the study of genetics, refers to a study that investigates how traits are passed from generation to generation. Understanding how genealogy works can help you further research your ancestry and learn more about your origins.

The Basic Process and Major Steps of Genetic Genealogy

Genetic genealogy uses DNA testing to help determine the relationship between different people. To understand precisely how this works, you will first need to understand a little about basic genetics.

Every woman has two X chromosomes, one X chromosome that she inherits from her mother and the other from her father. In contrast, men have one X chromosome and one Y chromosome. While men inherit their X chromosome from their mothers, they get their Y chromosome from their fathers. Thus, the father”s sperm always determines the gender of a fetus.

Based on these gender differences, along with other inherited chromosomal distinctions, DNA tests can be used to determine maternal and/or paternal relationships. The four most commonly used tests in genetic genealogy are:

  • Autosomal testing, which is frequently used for testing ethnicity or percentage of ethnicity
  • mtDNA testing (mitochondrial DNA testing), which is used to test the female lineage of a family (Because mtDNA is only passed to children through their mothers, this test can help identify whether two people share a common maternal ancestor.)
  • Y line tests,which look at short tandem repeats (or single nucleotide polymorphisms) to determine paternal heritage (A woman can use a close male relative, such as her father or brother, to help determine paternal lineage with a Y Line DNA Test).

What Genetic Genealogy Can Do for You

By taking DNA tests and learning more about your genetic genealogy, you can:

  • confirm some of your existing research
  • disprove or prove family legends or theories
  • learn more about which disease or conditions your genealogy tends to pass down
  • understand more about your family”s ethnic origins and evolution.

Genetic Genealogy Controversy

Although genetic genealogy can reveal some useful information, it is controversial because it can also uncover medical information that raises privacy issues. In addition, some are concerned that information gained from DNA testing will not be protected.

What Genetic Genealogy Cannot Do for You

While pursuing your genetic genealogy through DNA tests can tell you a lot about your ancestors and yourself, it does have some limitations. The following lists information that genetic genealogy will NOT tell you:

  • Because genetics is a relatively new branch of science, the database of those tested is still small.
  • DNA tests can prove a cherished family truth to be false. For example, if you have been told that you have Native American ancestors and testing shows that this is not the case, your feelings about your heritage can be seriously affected.While some may seek out these truths, others may be devastated when finding out they have grown up believing a misconception.
  • Genetic genealogy can”t provide you with information on all of the branches of your family.
  • Genetic genealogy can”t tell you anything about a common ancestor except that he or she existed. For example, DNA tests won”t be able to tell you about your ancestor”s cause of death.
  • Most DNA tests can only go back about ten generations, limiting the scope of your research.
  • While genetic genealogy can tell two people that they are related, it can”t tell them HOW they are related. For example, genetic testing can prove that two people have a common ancestor, but it can”t tell them whether they are first cousins.

Given the above drawbacks of DNA testing, it”s best to pair it with traditional genealogical research to get the most accurate and full account of your ancestors. Sources for genealogy research include:

  • a genealogy history institute
  • census records
  • courthouse records
  • family, especially older members
  • online genealogy search companies.

Resources

Bettinger, Blaine T., PhD. (n.d.). I Have the Results of my Genetic Genealogy Test, Now What? Retrieved March 13, 2008, from The GeneticGenealogist.com Web site.

DeForest, Jessica (2000). Untitled Document. Retrieved March 13, 2008, from the MSU.edu Web site.

Genetic Genealogist (2007). About Genetic Genealogy. Retrieved March 13, 2008, from TheGeneticGenealogist.com Web site.

Jesdanun, Anick (2007). Genealogy Web Sites Case Wide DNA Net. Retrieved March 13, 2008, from the MSNBC Web site.

Lei, Dr. Hsien-Hsien (2007). Author Jon Entine on Genetic Genealogy. Retrieved March 13, 2008, from the EyeonDNA Web site.

Linkroll.com (2007). Pros and Cons of Using Genetic Genealogy. Retrieved March 14, 2008, from the Linkroll.com Web site.