Documentation vs. DNA: The False Argument

“When documentation doesn’t exist, DNA tells us what’s what.” Or, at least, that’s the argument a genealogist posed in another forum.

Where do we begin with this?

For today, I’ll ignore the last five words of the quote and address the broader concept: Documentation always exists. Always. Even when we use DNA as “proof,” we still must have documentation.

The problem here is that the concept of “documentation” is misunderstood. “Documentation” is being misused as a synonym for direct evidence. It’s being used for “I’ve got ONE document that tells me what I hoped to find so I can just grab it and run with it.”

No. We can’t grab-and-run anything—even when it says exactly what we wanted it to say. That’s not what documentation is.

“Documentation” is not one source. Documenting an identity or a kinship requires a body of evidence. If we’re lucky enough to find that holy grail—the one document that “says so” in plain black and white—we still need supporting evidence to prove that

  • the individual named in that document is our person.
  • the claim in the document is correct.

So it is with DNA. We still need documentation. DNA may tell us that two people share a certain number of centimorgans and SNPs, but we still need documentary research—and a great deal of it—to determine HOW they are related. We still need a body of evidence to prove each identity and each kinship that is claimed in EACH generation—not just in our line but in the ancestral line of EACH match we’re using in our claim that DNA “proves” this-or-that. 

The bottom line:

Documentation always exists. That documentation often does not include direct evidence, in which case we build a case using all types of evidence. DNA is one of the types of evidence we use to build that case. DNA is not a substitute for other types of evidence. It is not a crutch to use so we can get by without using the record troves that aren’t convenient to use. Deoxyribonucleic acid (aka DNA) is a building block and one block alone does not make a person or proof.

IMAGE CREDIT: "Man Holds Scales Decision," PresenterMedia ( : accessed 28 July 2018), item 20993; used under license.


HOW TO CITE: Elizabeth Shown Mills, "Documentation vs. DNA: The False Argument," blog post, QuickTips: The Blog @ Evidence Explained ( : posted 28 July 2018).