05 March 2019

DNA Standards - Part 4

For "DNA Standards - Part 1" see https://debsdelvings.blogspot.com/2019/03/dna-standards-part-1.html. In the first part I paraphrased the standards for using DNA evidence for genealogy into bullet points.

This is the post for "DNA Standards - Part 4."


Prior bullets are discussed in other parts of this series:

In "DNA Standards - Part 4" I further discuss the fifth bullet. The main bullet indicates considerations when using DNA to help answer a research question; sub-items explain what is needed to accomplish the tasks defined in the main bullet:

  • ensure enough people have tested to support the conclusion (Standard 53)
    • may require documenting living descendants from multiple children of a focus ancestor or ancestral couple then asking them to test
    • in general, the more generations back to the hypothesized common ancestor or the more possible shared lines, the more test takers needed
    • no one can say that, in all circumstances, you need two or three or six pieces of documentary evidence to have strong evidence for a conclusion because no one knows ahead of time what information will be found in which sources or how credible that information will be; the same applies to DNA evidence
    • exactly how many test takers are needed will vary depending on how many generations it is back to the hypothesized common ancestor and how many lines are traced down from those ancestors
    • consider whether additional tests or higher resolution tests for those test takers found in earlier research might more strongly support a conclusion

Additional bullets will be discussed in other parts of this series:

BCG, Genealogy Standards, 2nd ed. (Nashville: Ancestry, 2019)


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All statements made in this blog are the opinion of the post author. This blog is not sponsored by any entity other than Debbie Parker Wayne nor is it supported through free or reduced price access to items discussed unless so indicated in the blog post. Hot links to other sites are provided as a courtesy to the reader and are not an endorsement of the other entities except as clearly stated in the narrative.

To cite this blog post:
Debbie Parker Wayne, "DNA Standards - Part 4," Deb's Delvings, 5 March 2019 (http://debsdelvings.blogspot.com/ : accessed [date]).

© 2019, Debbie Parker Wayne, Certified Genealogist®, All Rights Reserved


  1. Love these posts! Thank you.

  2. Thanks, Ann. I'm glad these are helpful. Sometimes just rewording into normal language instead of the more formal phrasing in the manual is useful.