Hiring a DNA Testing Company

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DNA testing has become an accepted tool for identifying ancestors and for verifying genealogical leads. It is also used frequently to learn about our deep ancestry. Testing your family DNA sometimes results in finding cousins who may have more genealogical information than you.

What is DNA?[edit | edit source]

To better understand DNA testing it is helpful to have a basic understanding of how DNA is inherited. The University of Utah's Genetic Science Learning Center's page Basic Genetics is an excellent resource.

DNA is based on the 46 chromosomes that every human being has (with few exceptions). The sex-determining chromosomes are X from the mother and either X or Y from the father. If X from the father, the child is female (XX) and if Y from the father the child is male (XY). The Y-chromosome can be traced from father to son to son and so on.

In addition, each human being carries a genetic molecule in their cells called the mitochondrial DNA (mtDNA). This genetic component is found in organelles called mitochondria, which produce energy for the hosting cell. mtDNA is inherited exclusively along the mother side. Both males and females carry mtDNA, but only women will pass their mtDNA to their children. Both mtDNA and Y DNA can go back hundreds of years, because of their slow mutation rate. They can be used to help verify or find direct maternal or paternal lines.

Autosomal DNA is the DNA found on the rest of your 44 chromosomes. It is a mix of all your ancestor lines not just your direct maternal or paternal line. Autosomal usually shows about 6-7 generations back.

DNA Double Helix.png

Getting Started with DNA Testing[edit | edit source]

CeCe Moore's "DNA Testing for Genealogy - Getting Started" series is a great place for beginners. It is also great for helping to decide which type of DNA test to do. Read her posts at the Geni blog:

Y-DNA Testing[edit | edit source]

Information stored in the Y chromosome (Ycs) passes virtually unchanged from father-to-son for centuries. Analysis of this genetic information, found in living people, can help you determine whether you share a common paternal ancestor with another person alive today. Based on the number of genetic markers shared on the Ycs with another person, you can also estimate how many generations in the past your common paternal ancestor lived. This is called Time to the Most Recent Common Ancestor (TMRCA) and it is based on a mutation rate calculated on many thousands of father/son pairs. Ycs testing can help in verifying a common paternal ancestor, or learn about the origin of a particular surname. Additionally, each Ycs can be predicted into a specific branch of the large Ycs tree based on the set of Short Tandem Repeats (STRs) tested by many companies and using an online predictor, or it can be accurately assigned to one of these branches through the test of Single Nucleotide Polymorphisms (SNPs) (see the Ycs ISOGG tree).

Note: Only males carry the Ycs, but a woman can have a male relative tested in her stead to obtain such information.

MTDNA Testing[edit | edit source]

Mitochondrial DNA (mtDNA) is a small circular genetic molecule found outside the nucleus in organelles called mitochondria. It is inherited exclusively from our mothers and it follows an unbroken maternal line. MtDNA is helpful in verifying the existence of a common maternal ancestor or to study the ancient origins of our maternal line. MtDNA lineages can be grouped together in a large mtDNA tree. Each branch of this tree may have a specific geographic distribution that might help someone locate the country or region of origin of their maternal line.

MtDNA testing can be done for a small section of the genome called the control region (which usually include the segments HVR1, 2 and/or 3), or for the full molecule (16569 bases). Family Tree DNA is currently the only commercial laboratory offering the complete mtDNA sequence to its customers.

Note: Although mtDNA is inherited exclusively along the maternal side, both males and females carry it. Only females will pass it on to their children. ISOGG has a useful diagram which shows the path of mtDNA transmission.

Autosomal DNA Testing[edit | edit source]

Autosomal DNA is the DNA found in the 22 pairs of nuclear chromosomes. They are shuffled at each generation and only half of it is passed to our offspring. It does not follow a clear and straight path of inheritance as the Ycs and mtDNA described above. However, current testing provides a survey of one million or more sites on a person nuclear genome. This information is helpful in identifying recent cousins within the last five generations, or the ethnic origins of our family tree. Companies like 23andMe, Family Tree DNA, and Ancestry all offer autosomal testing for genealogical purposes. The Genographic Project recently launched an autosomal test that offers insights into our deep ancestry. These tests offer a lot of information about our DNA and they may be difficult to understand. Each company offering such tests has numerous tutorials and aids on their website to assist with the interpretation of such results. 

ISOGG's "Autosomal DNA testing comparison chart" provides useful information for selecting a company to process your atDNA.

DNA Testing Companies[edit | edit source]

Some major commercial DNA testing companies are listed below in alphabetical order. Please visit their websites to learn more about their services:

23 and Me

  • Autosomal (with paternal and maternal Haplogroup assignment)
  • Ability to connect with people who are DNA matches
  • Offers health test
  • Chromosome browser feature
  • No tree feature at this time


  • Autosomal
  • Ability to connect with people who are DNA matches
  • Physical traits feature

DNA Consulting

  • STR markers (form of autosomal)
  • Y-DNA (25 markers)
  • mtDNA

FamilyTree DNA

  • Autosomal
  • mtDNA (with maternal Haplogroup)
  • Y-DNA (37 markers through 111 markers with paternal Haplogroup)
  • Ability to connect with people who are DNA matches
  • Chromosome browser feature

Living DNA

  • Autosomal (with paternal and maternal Haplogroups)
  • no tree feature at this time


  • Autosomal
  • Ability to connect with people who are DNA matches
  • Chromosome browser feature

Public DNA Databases[edit | edit source]

Defunct Public DNA Databases[edit | edit source]

  • Mitosearch - Site closed in May 2018 over concerns their data was not compliant with the European Union's General Data Protection Regulation (GDPR)
  • mtDNACommunity - As of August 2020 the site is down, but you may be able to contact them at info@mtDNACommuity.org
  • Sorenson Molecular Genealogy Foundation (SNGF) - Formerly sponsored by Brigham Young University, SMGF was acquired by Ancestry. The data is not publicly available.
  • YSearch - Site closed in May 2018 over concerns their data was not compliant with the European Union's General Data Protection Regulation (GDPR)

Genetic Genealogy Standards[edit | edit source]

In 2015, a group of expert DNA genealogists developed a set of standards to help people accurately interpret their DNA test results. The standards are available on the group's website The Genetic Genealogy Standards.

Result Analysis[edit | edit source]

Organizations, such as The Genetic Genealogist, The Genetic Genealogy Consultant, and Your Genetic Genealogist provide services to help you interpret your DNA results and get the most out of what they can tell you about your roots.

DNA Projects[edit | edit source]

Thousands of DNA Projects, usually focused on a particular surname, location, or ethnicity, are active around the world. A listing of geographical projects can be found in the ISOGG Wiki.

Examples of individual projects include:

FamilyTree DNA has several projects, including the following:

A list of FamilyTree DNA projects can be found on their FamilyTreeDNA Group Projects page.

Adoption-Specific Projects[edit | edit source]

These projects have created with the specific purpose of helping adoptees find their biological families.

Websites[edit | edit source]

Wikipedia has more about this subject: Genetic genealogy

Disclaimer[edit | edit source]

Neither The Church of Jesus Christ of Latter-day Saints nor FamilySearch International is associated in any way with any DNA study. As a non-profit organization, FamilySearch cannot recommend a specific DNA-testing company to you.