A Look at DNA in Genealogy

Posted January 27, 2011 by Amanda | 6 Comments

Although DNA testing has been around for a while, only recently have genealogists started using DNA to help trace the origins of their ancestors. While DNA testing cannot give you specific information (names, dates etc.), when used in conjunction with your other research, genetic testing can help us prove/disprove ancestral lines while also leading us in possible new directions to pursue. Let’s take a quick look at how DNA testing can help you trace your ancestry.

Now that the technology is a little bit more affordable, you can order your own home DNA kit over the internet (prices can range from $100 – $400). These kits usually include a cotton swab to swab the inside of your cheek. When you send your samples for testing, researchers look for matching markers to determine level of relation. You can go here for a better understanding of the basics of DNA.

There are two types of DNA testing available:

Maternal lineage – mDNA

Mitochondrial DNA is passed from the mother to the child. Therefore, all offspring will share the same mDNA as their mother, and her mother, and her mother’s mother and so on. If a match is found while testing your mDNA with others, chances are you share the same common female ancestor.

Paternal lineage – Y-chromosome

The Y-chromosome is inherited through the paternal line between father and son. Markers on the Y-chromosome can help determine if a common ancestor is shared. So, if you want to trace your mother’s paternal line, you will need a DNA sample from either her father or her brother.

What can DNA tell you?

  • Discover living relatives – You can learn if you are related to specific people and possibly learn your most recent common ancestor. The results won’t tell you a specific name, but it may help you narrow it down to a couple of generations.
  • Learn if people sharing a common surname are from the same lineage – DNA can let you know if your related to others who share your surname.
  • Map genetic origins of large population groups – Your results may help illustrate your ancestral and ethnic origins and let you trace their migration throughout the world.
  • Provide locations for further genealogical research – Comparing your results to population studies may help point you to a new geographical area to research
  • Prove or disprove existing genealogical research/theories regarding your ancestry

You can also enter your results into larger DNA databases, such as The Genographic Project, to compare your results with others who have already been tested. You never know if you might find a match!

Post written by Amanda

Amanda is the Social Media Coordinator at Geni. If you need any assistance, she will be happy to help!

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  • Scott Sherris

    Amanda, with the rapidly advancing technology of DNA testin, at least one compant, FTDNA, is doing autosomal (non-sex chromosome) testing and is using some serious computin algorithms to identify matches on both sides. now we’re not just limited to just the straight paternal or maternal line, but everythin in between.

    • http://twitter.com/GeniGrant Grant Bru00fcnner

      I’m a big 23andMe fan. I have a big post in the works about it.

  • http://www.facebook.com/profile.php?id=678834304 Kent Karlsson

    I’m also on 23andme, and I feel like the article is describing what it was like a few years ago. After testing SNPs across all chromosomes, you can find potential relatives even if they aren’t on a direct maternal or paternal lineage. Exciting stuff, even if its hard to find the relation after you’ve made a match. I have connected with 60 matches but have yet to find a common ancestor with one of them.nnWish Geni would be able to combine DNA testing with the tree! It tells you that this profile is related to you and then if both agrees you can see each others ancestors!

  • http://www.facebook.com/david.zusiman David Zusiman

    Unfortunately, only FTDNA users can donate their genetic data to the Genographic Project. why can’t they collborate with 23andme (big fan here too!) and get exposed to other tens of thousdands of genetic data

  • Nicholas Curry

    Here’s a tricky one… Does the maternal line include the x passed from one’s maternal grandfather?n

    • Nicholas Curry

      When a mtDNA test is performed