DNA Explained

What is Genetic Genealogy?

Genetic genealogy is the application of genetics to traditional genealogy. Genetic genealogy involves the use of DNA testing to determine the level of genetic relationship between individuals.This field of science has grown substantially over the last decade led by the vast amount of public participation and academic research.  The amount of knowledge that has been gained has improved our understanding of how genetics can help us in our genealogical research.

Genetic Genealogy has the following meaning;

  • It follows a very tight set of criteria.
  • It looks at a 500 to 1,000 year time frame where there is a chance of historical documentation.
  • It follows the paternal Y-DNA and the maternal mitochondria DNA ( mtDNA)
  • It starts by comparing men with the same surname

What is DNA?

So what is DNA (DeoxyriboNucleic Acid)? DNA is a chemical consisting of a sequence of hundreds of millions of nucleotides found in the nuclei of cells. It contains the genetic information about an individual and is shaped like a double-stranded helix.For the larger scientific explanation see the links at the end of this page.

Think of DNA testing as a tool for us to add to our genealogy toolbox.  A tool as valuable as the computer and the internet which have become invaluable for us in our genealogy research. DNA testing is not a stand alone process which will tell us everything we want to know about our ancestral line.  DNA testing works hand in hand with the family history information you know.  DNA testing will not automatically compute a missing ancestors name for you.

The use of DNA testing can provide us additional  information for our family history research.  It asks the question. how well does my research hold up to the results of a DNA test?  A DNA test can confirm, redirect, or show errors that are within our family history data such as crossed up family lines.

The commercial genetic genealogy field was started by Family Tree DNA (FTDNA) in 2000 with two entrepreneurial genealogists from Houston, Texas.  Bennett and Max had the same inquisitive questions about the possibility of using the new science of DNA to answer their genealogy questions.  They made contact with Dr. Hammer at the University of Arizona, at Tucson who is one of the worlds leading population genetics.  Out of this FTDNA was born with it operating the businesses and Dr. Hammers lab providing the lab for processing the DNA tests.  FTDNA has grown right along with the genetic genealogy field to include a full range of DNA tests.  FTDNA also has developed its own research lab, in Houston, Texas, for conducting advance scientific research which is helping to moving our field of science further along.

We start Y-DNA testing with surnames because this gives us a historical reference to start our research within. A time frame where there is a chance that some historical documents are available to match with the Y-DNA results.  It also means that if a male line has stayed pure from the origin of a given surname then all descending men will have the near identical Y-DNA results.  The small mutational changes in the pure male line then become markers to help determine branches within that male line.

The  power of the Y-DNA is that it is passed down from father to son through time almost unchanged but for the random mutation. The mtDNA is passed from a mother to all her children but is only passed forward by her daughters.  The Y-DNA follows the paternal side and the mtDNA follows the maternal side.

What can a DNA study achieve?

It can:

  • Validate research
  • Find any mistaken connections in existing knowledge
  • Determine which family branches are related
  • Bridge gaps in the paper records
  • Confirm or find previously unknown name variants
  • Sort out multiple families found in the same location
  • Discover information which may solve research problems, and/or resolve brick walls
  • Confirm or get clues regarding migrations
  • Confirm suspected events, such as illegitimacy and adoption
  • Discover information to define the major branches of the tree going back to the origin of the surname
  • Discover information about the evolution of the surname
  • Discover clues regarding the origin of the surname
  • Combine results with research in early records to determine the number of points of origin for the surname

The Y-DNA is examined. The depth of the test is dependent on how many markers of the Y chromosome are examined. The more markers that are examined, the more accurate but more costly the test.

How much is the cost?

As at September 2011 the One Name Study Rates for tests done by FamilyTreeDNA are:

Males Y-DNA

  • 12 Markers – $99
  • 25 Markers – $124
  • 37 Markers – $149
  • 67 Markers – $238
  • 111 Markers – $339

Female mtDNA starts at $99

The above prices change from time to time as there are often special prices that are announced. For up to date prices, please go to Family Tree DNA.

What is the testing process?

A small kit is sent out which contains a small brush which is used to take a swab sample from inside the cheek. The brush is sent back in a protective wrapper to the laboratory for analysis.

How long until results?

Presently, we suggest new project members do a 37 Y-DNA marker test. The initial results are usually available in six weeks. Then, you may elect to test additional markers.

Will I have an instant match?

Participants need to be aware that not everyone will receive an instant DNA match with someone of their same surname.  Many reasons account for this fact.  The following are some reasons that have affected participants in the McCubbin DNA Project:

  1. Someone of the same DNA signature has not yet tested (there is a big ocean out there with many different schools of fish)
  2. An unknown adoption happened somewhere along ones male line
  3. Crossed-up or inaccurate family history information occurred (there is a lot of bad family data out there that is being copied without asking and checking its accuracy)
  4. The change of ones surname (for a variety of reasons) at a point in the past has broken a direct biological male line for a given surname that is in use today
  5. A non-paternal event somewhere along the male line took place (i.e., unexplained birth, fidelity issues, war, etc.,)

How safe is a persons DNA record?

No individual is personally identified, unless they wish.  Only the DNA study co-ordinators and the laboratory undertaking the test will know the identity of the individual. The test results and identities of project members are shown only on password protected web pages, and only if they have granted permission for their names and results to be revealed to others who are close matchesThe results of the DNA test do not reveal any medical data. The DNA evaluated in this test is often called junk DNA because of its lack of medical information. Nor can it be used for criminal investigations.

 

Resources for More Info on Genetic Genealogy & DNA Testing
There are many places on the web to learn more about genetic genealogy and DNA testing.  Doing a Google search on genetic genealogy will list numerous web sites.  Below are links to some good sites, along with some books, where you can learn more on genetic genealogy and DNA testing.

DNA 101 – Good simplified explanation about DNA for genealogy.
Family Tree DNA – has an excellent learning center with videos.
Molecular Genealogy – Series of videos on genetic genealogy.
Kerchner’s DNA Testing & Genetic Genealogy Info. and Resources
Genetic Genealogy: Using DNA Testing for Family Research
International Society of Genetic Genealogy – See the Resources link.

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