Start My Family Tree Welcome to Geni, home of the world's largest family tree.
Join Geni to explore your genealogy and family history in the World's Largest Family Tree.

DNA Primer - A portal for genetic genealogy

« Back to Projects Dashboard

Project Tags

Genetic genealogy is a hot topic, but many people are put off by the learning curve. This is a place to get answers to your questions.

This project is sponsored by Geni's curators to provide a very brief introduction to the complex field of genetic genealogy.

There are three sub-projects:

How to participate

  • If you want to see the discussions from this project in your Message Center, click Follow.
  • If you have a question, start a discussion (or add on to an existing discussion). The curators and users who are interested in DNA testing will try to get you an answer.
  • To start a discussion, click the Project Discussion link in the upper right corner. Geni will take you to the Discussions page. Click Start a Discussion.
  • If you're a whizz at genetic genealogy and you want to help, consider becoming a Collaborator.

Terminology

For a list of basic terms, see this Glossary maintained by the International Society of Genetic Genealogy.

One of the barriers to understanding genetic genealogy is the scientific jargon. People who try to understand the terms first frequently have a harder time grasping the basic concepts than those who start by taking the take the terms at face value.

Questions and answers

Why would I want to get a DNA test?

Genealogy is about proving family relationships. When you get a DNA test you have the opportunity to compare your results to the results of other people who have been tested. The comparison has the potential to prove (and disprove) family relationships.

See the DNA Testing project for more information about potential benefits and limitations.

Who can be tested?

Any living person can get a genetic test. There is currently no easy way to test hair or fingernails, so it is not possible to get results for someone who is dead. In some countries, such as France, the law prohibits genetic tests except under the supervision of a doctor.

Are there privacy risks?

No test is absolutely free from privacy risks, but :

  1. Testing companies have privacy policies that prevent them from making your results public without your permission
  2. Genetic tests for genealogy aren't high enough resolution to be used as paternity tests
  3. Genetic tests for yDNA and mtDNA do not reveal medical conditions
  4. U.S. law prevents insurance companies and employers from using genetic tests to deny coverage, raise premiums, or refuse employment
  5. Your genetic sample cannot be used to clone you

How do I get a test?

Order a kit from a testing company (see below). Kits are usually free. You send payment when you return your sample.

What kind of sample do I have to give?

The most common way to take a sample is to use a special brush to brush the inside of your cheek. Some of the dead cells from your cheek stick to the brush. You put the brush in a special bottle provided by the testing company, and mail it back.

How long does it take?

The amount of time varies. One to three months is common. It depends on the company and on their current workload.

What do I get?

Test results are in the form of a scientific shorthand. Most people need additional help to understand what their results mean.

What tests are available?

For genealogical purposes there are three kinds of tests:

  • yDNA, for the male line - tests the y-chromosome, which is inherited by men from their fathers.
  • mtDNA, for the female line - tests the mitochondrial DNA in the cells, which is inherited by children from their mothers.
  • Autosomal DNA, for relatives on both sides within (about) the past four to seven generations - tests the autosomal DNA, which is inherited by children from both parents. (Autosomal DNA also called nuclear DNA or recombinant DNA.),

Where can I order a test?

The main goal of testing is to find genetic matches, so it is important to choose a testing company that has a very large number of existing customers. Curators have had positive experiences with these companies:

  • 23andme. They offer a combined yDNA, mtDNA, and autosomal test, but you will not be able use the yDNA and mtDNA information they give you to compare results with other genealogists. You can, however, use the autosomal information to find close matches with other 23andme customers and at other 3rd party sites.
  • Geni. They offer a yDNA, mtDNA, and autosomal ("Family Finder") tests. The data from their tests can be used to find matches with other FTDNA customers and at other 3rd party sites.
  • Family Tree DNA. They offer a yDNA, mtDNA, and autosomal ("Family Finder") tests. The data from their tests can be used to find matches with other FTDNA customers and at other 3rd party sites.

There are many other testing companies. To get an opinion, post a message asking for more information.

How much does it cost?

Pricing varies, but is generally dropping as more people get DNA tests for genealogy.

  • 23andme offers its combined yDNA, mtDNA, and autosomal test for $99 (2014).
  • Family Tree DNA offers its autosomal ("Family Finder") test for $99 (2014). Introductory level yDNA and mtDNA tests are $59 each (2014). You can upgrade later to a more comprehensive test. You might be able to get a small discount by ordering your test through an existing project. The company also offers special sales throughout the year. The most significant sale is during the November - December holiday season.
  • Geni offers its autosomal ("Family Finder") test for $99 (2014). A combined yDNA and mtDNA test is $198 (2014).

How do I decide what kind of test to get?

See the DNA Testing project for more information about testing strategies and choosing the right test.

What else can I do with my test results?

  • GEDMatch, upload your raw data file from FTDNA's Family Finder or from 23andme to look for matches with other people
  • mitoSearch, enter your mtDNA results to look for matches with other people
  • ySearch, enter your yDNA results to look for matches with other people
  • Genographic Project, take a test or transfer your results to contribute to National Geographic's study of human origins and migration

Where can I learn more?

There are thousands of basic introductions to genetic genealogy on the Internet. Try some of these: