DNA and Genetic Genealogy

DNA has been a popular topic of discussion in recent times due to advances in DNA testing technology. This allows for the usage of tests in genealogy research, or genetic genealogy. Below is an overview of what DNA is, how genetic genealogy works, and the possible issues arising from this kind of research.


DNA (deoxyribonucleic acid) is a self-replicating molecule in the shape of a double helix that contains the genetic code for organisms. It is present in most cells of humans and animals. DNA contains information for development, functioning, growth, and reproduction. It is hereditary, passed down from parent to child over the course of generations.

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Genetic Genealogy


Genetic genealogy uses DNA testing and genealogy research to see if people are related. It is more popular now due to improved DNA testing technology and the availability of home testing kits.

Home Testing Kits

The below is being provided for informational purposes only. The BPL cannot recommend or endorse any particular home testing kit.

DNA home testing kits are available to consumers from companies like 23 and Me, Ancestry, Family Tree DNA, Living DNA, and My Heritage. The types of tests and services provided by each company varies, as do the prices for the kits. Home tests usually involve filling a container with saliva and mailing it back to the company for testing. Results will be available on the company’s website, for which the consumer will have registered for an account.

Types of Tests

  • Autosomal – Uses autosomal chromosomes from both parents to determine a person’s ethnic background. It can be taken by any gender, and does not determine haplogroups. This is the test most frequently used by genealogy researchers.
  • mtDNA – Traces a person’s maternal ancestry by testing mitochondria, which are passed down from mother to child. It can be taken by any gender. It also determines the test taker’s maternal haplogroup, an ancient group of people from which they descend on their mother’s side.
  • Y-DNA – Traces a person’s paternal ancestry by testing the Y-chromosome, and can only be taken by those that have a Y-chromosome. It also determines the test taker’s paternal haplogroup, an ancient group of people from which they descend on their father’s side.

Companies Selling Tests

  • ​23andMe- Autosomal, mtDNA, and Y-DNA
  • AncestryDNA- Autosomal
  • Family Tree DNA- Autosomal, mtDNA, and Y-DNA
  • Living DNA- Autosomal, mtDNA, and Y-DNA
  • MyHeritage- Autosomal

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Forensic Genetic Genealogy

Forensic genealogy uses DNA profiles to identify unknown people, including victims of crime and suspected criminals.

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Family Secrets

Home testing has led to the revelation of a lot of family secrets, some of them painful. Many have found that one or both of the parents that raised them were not their biological parents. Others found half-siblings or other close relatives that they did not know existed. Some found evidence of relationships in the past that completely changed who and what they thought their family was. These discoveries have led to serious conflict for many families.

Criminal Investigations

Forensic genealogy has led to many breakthroughs in cold cases all over the U.S. While some think this is a good thing, others believe it is a violation of privacy and should either be restricted or not done at all. Some testing companies have changed their policies and only allow law enforcement to access DNA profiles after getting a warrant.

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