Unexpected DNA Matches: When DNA Testing Reveals Family Secrets

You’ve taken a DNA test and found one or more unexpected matches. Buckle up: your family history is a bit more…complicated than you’ve been led to believe.

You’re about to learn that your family tree has more roots, branches, twigs, and leaves than you realized.

This could rock some boats. Shake some family trees. Ruffle some…you get the idea.

On the positive side, an unexpected match could offer new beginnings and the chance to explore uncharted territories. You may make new connections, discover new family members, and gain considerably from the experience.

Turbulence isn’t always bad. But it is rough for a while.

Unexpected DNA Matches Quicklinks

Unexpected DNA Matches Almost Always Unearth Family Secrets

Adoption. Premarital sex. Infidelity. Desperation.

Family discoveries wrought by DNA testing results can open doors that some family members would have preferred to keep tightly locked.

DNA tests can bring to light episodes in our parents’ (or their parents’, or their parents’ parents’, etc) lives that they’d prefer remained under wraps.

Just remember: your mother, father, or other family member (whoever has chosen to keep the secret) is not the villain here. Instead, they’re just another flawed human.

When DNA Tests Reveal Unexpected Paternity

As we recently wrote in “My DNA Doesn’t Match My Father? When Your Dad is Not Your Dad,” the man you’ve always known as Dad may not be genetically related to you. Instead, you may learn that some other man, a total stranger, is your biological father.

That’s a big deal.

When Grandparents Misbehave(d)

Grandparents may have misbehaved as a cause of unexpected DNA matches

Maybe it wasn’t your mom who got frisky; maybe the hidden paternity occurred further down the family tree.

As one respondent wrote on Quora, you may discover that one of your grandparents has no genetic relationship to you.

I’m somewhat dark-skinned for a native Englishman: mediterranean light brown & tan easily…My father was similar complexion…BUT his father was different: short, round, very, very pale – as a kid I remember him as almost highlighter pink because he got sunburn so easily…

When I got the ancestry report back it was 75% Northern European (specifically English) and 25% middle east …

We’ll presumably never know the story.

Did Grandma have a fling? If so, with whom?

She was very snobbish and class-conscious, so if it was an affair it would have been with someone “posh”.

Was she raped and it was covered up?

(Rupert Baines, August 28, 2018, responding to “Has anyone ever taken a DNA test and found something completely shocking?”)

While Rupert will probably never learn the true story (apparently his grandparents are deceased), his scenario is far from unusual. Family histories tend to be messier than they appear on the surface.

When Family History Rumors Turn Out Wrong

Another Quora respondent, LeeAnn Gerleman, threw in a twist: the great-grandfather assumed to be “the product of a rape or an affair” who actually wasn’t.

Throughout the last 150 years, it was well known in our family that my gr grandfather was the product of a rape or an affair. His legal father left the family because he could not handle it…

(The presumed affair or rape involved someone of Native American ancestry)

LeeAnn took the AncestryDNA test and “realized, ‘wait a minute! There’s no…[Native American] here at all!’ I am 71% Irish, 18% German and 3% Swedish.”

LeeAnn’s biological brother took a DNA test as well, and had the same result.

LeeAnn and her brother both had an unexpected DNA match: their great-great-grandfather actually WAS their great-great-grandfather, contradicting a century and a half of established wisdom.

Aunts, uncles, cousins were all shocked. On my family tree on ancestry, I have a dna link with this [great] grandfather’s paternal grandmother. so his legal father was his real Dad.

Whether the unexpected match throws your paternity into question, or reveals some other long-buried family secret, the surprise and shock are going to make family gatherings…interesting.

When Secret Adoptions are Unearthed

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Unexpected DNA matches can reveal adoptions that were hushed up. Whether you’re the adoptee discovering the fact for the first time, or you’re just learning you have a biological sibling whom your mother gave up for adoption long ago, secret adoptions can be tumultuous when brought to light.

Take the case of Ann-Marie. “I was 33 when I learned about my older sister,” she describes on Quora, “and outraged my mom had lied (by omission) about it.”

Or Brenda, who was given up for adoption and learned at age 58 that “my birth father never told his children” about her. “My siblings were more upset that I was kept a secret,” she recalls.

Hopefully, with grace and tact, you and your family can grow through the rough patch and emerge stronger.

As Ann-Marie and Brenda indicate, it’s often the secrecy—with its accompanying feeling of betrayal—that hurts more than the fact of the adoption itself. Often, learning that you have siblings (or half-siblings) who are new to you can be exciting and adventurous.

An Unexpected DNA Match is Biologically Your Family

Whether an undiscovered half sibling or a half uncle, your DNA matches are genetically related to you. DNA results don’t lie, and the top DNA testing companies have very high accuracy rates.

In short, you won’t see family members in your list who married in, may have been adopted, or are otherwise not biologically related to you. These are your biological family members.

Shared DNA—whether of identical twins, first cousins, parent and child, great-grandparents, or half sisters—is absolutely authoritative.

Unlisted Unexpected Matches

DNA testing companies don’t share results with one another; there is no central DNA database. Instead, there are multiple DNA databases, owned and controlled by different private corporations. The following are just a few of the at-home DNA tests on the market.

  • AncestryDNA
  • 23andMe
  • LivingDNA
  • TellmeGen
  • MyHeritage
  • FamilyTreeDNA

If you take an AncestryDNA test and don’t see any unexpected DNA matches, that doesn’t mean they don’t exist. It just means they haven’t taken the AncestryDNA test. Maybe they’ve taken the 23andMe test, maybe one of the other tests, maybe no test at all.

(Check out our review of the DNA test titans: 23andMe vs AncestryDNA)

See, things can get messy in the world of DNA testing.

To simplify matters, let’s assume that you’ve taken an Ancestry DNA test and are looking at your list of matches.

What to do if you find an unexpected DNA match

If you and your family members take a DNA test, and an unexpected DNA match turns up, the following guidelines will help everyone to come through it with the least amount of kerfuffle.

Don’t Put Too Much Weight In The Relationship Estimate

When you take a DNA test and find DNA matches, the testing company (e.g., Ancestry, 23andMe, MyHeritage, etc.) may provide a relationship estimate or “predicted relationship” between you and the match.

Don’t put too much trust in it. The estimate is based on genetic relatedness, which is measured in centimorgans (centimorgans essentially measure how much DNA you share with someone). The trouble is, different family members can share similar centimorgan measurements with you.

Unexpected DNA matches - Origins Genealogy

Identical twins share 2300-3900 centimorgans, but a parent-child relationship also falls in that range at around 3,275 centimorgans.

A half sibling would share between 1,450 to 2,050 centimorgans with you. So would a niece, nephew, aunt, uncle, grandparent, or grandchild.

First cousins can share anywhere between 680 and 1150 centimorgans. But a half-niece, half-nephew, half-uncle, or half-aunt would share a similar centimorgan range.

Bottom line: the “predicted relationship” given by the testing company could be wrong. When you look at your DNA match list, use your best judgment (or get a professional opinion from a DNA expert) before jumping to conclusions.

Should You Tell Your Family About the DNA Match?

Telling your family about the DNA match should be undertaken with care. In most cases, telling them is probably the right choice, but there could be certain scenarios in which it might be better not to.

Take time to make sure you’ve got your facts straight. Imagine the embarrassment and outrage if you “reveal” an affair or adoption only to later realize you were misinterpreting DNA evidence. Spare your family unnecessary upheaval.

If, after careful consideration, you don’t have a compelling reason NOT to tell your family about the DNA match, radical honesty is probably the best policy.

If you do go ahead with telling your family, keep the following guidelines in mind.

Navigating the Turbulence of Unexpected DNA Matches

Unexpected DNA match - Origins Genealogy

  1. Remain calm and rational. Strong emotions will only complicate what is a delicate situation. Be sure that you are interpreting the data correctly before you broach the subject to others in the family.
  2. Treat the secret-keeper(s) with kindness and respect. You may be furious that they have kept this secret, but they were probably doing what they thought was best. It’s OK to acknowledge your feelings of betrayal, but you should simultaneously remember their humanity.
  3. Engage in open dialogue, remaining as neutral as possible. Even though you’ll feel strong personal feelings, this situation is not personal to you: it affected you but was not deliberately done to you. It was caused by flawed humans trying to muddle their way along, as are we all. Keep this impersonal mental frame as you open discussions with your family members; be the rock they can lean on if things get emotionally fraught.
  4. Engage a professional genealogy service, if you choose. Such a service can make sense of the discovery and also help smooth matters out between family members. A good genetic genealogist can help with the following:
    • Interpret the test results to help you conclusively understand the relationship of your genetic match to you.
    • Upload your DNA test results into additional DNA databases to build a more full picture (and potentially identify more matches).
    • Mediate between family members by showing conclusive evidence of the genetic relationship, and by explaining the story of the relationship in an impartial, experienced, and professional matter.

Embrace the Adventure of Shared DNA!

You can’t put the DNA cat back in the bag. You’re on the rollercoaster whether you want to be or not. You might as well enjoy it.

Here at Origins Genealogy, many of our customers tell us that meeting a new family member has been one of the best experiences of their lives.

Origins Genealogy Can Help

If you are thinking of taking a DNA test, or if you’ve taken one and have already had your world rocked by unexpected DNA matches, let the experts at Origins help you.

We are a professional genealogy firm with specialization in the area of genetic genealogy. Genetic genealogy lives at the intersection of traditional genealogy and cutting-edge genomics, and represents the best possible set of skills for solving thorny family tree conundrums.

Ways Origins Can Make Your Process Easier

Origins Genealogy can assist with your DNA discovery journey in the following ways:

  • We can assist you in setting up your Ancestry.com account and obtaining your DNA test kit.
  • Once you receive your DNA results, we can download a copy of your raw DNA and upload it to four other DNA databases to ensure maximum coverage and connections.
  • We can help you analyze and make sense of your DNA results and DNA matches. Genetic relationships are often not well defined in the test results, and are subject to misinterpretation. Our skilled genetic genealogists can cut through the noise.
  • We can serve as a professional liaison between biological family members who have never met. Whether it’s you and an adopted sibling meeting for the first time, you meeting your biological father, or any other sort of first-time meeting, tensions are often high. Origins can help by proving to both parties that the genetic relationship is genuine, and by relaying and allaying any concerns in advance of the meeting so both of you can be comfortable.

To learn more about how Origins can help your situation, call 801-500-0900 or email [email protected]

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Read next: How to find my birth mother, the latest article from the Origins Genealogy experts.

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