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DNA Results

Can DNA testing be wrong? The short answer is no.

Did your DNA results come back surprising or confusing? You are not alone. This happens to thousands of people every month. Here's what it means, and what to do next.

Note: our free DNA help is for adults (18+) trying to understand results that may lead to identifying their birth parent(s). For other searches, please see our Hire a Professional page.

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DNA testing with companies like AncestryDNA and 23andMe is virtually never wrong. But results can be confusing, and that's where we come in.

When results can mislead

The rare cases where DNA can be misinterpreted

Contaminated Sample

DNA samples can be contaminated or degraded, which can affect accuracy. If a sample is collected from a surface touched by multiple people, results may be harder to interpret. This is rare with modern consumer kits, but it does happen. The testing company can often retest if you have concerns.

Laboratory Error

Even with strict protocols in place, there is always the possibility of human error or technical issues. Most consumer testing companies use multiple redundant measures to prevent this. It's extremely rare, but not impossible.

Single Marker Tests

Tests relying on a single genetic marker, like Y-chromosome or mitochondrial DNA only, are less precise. Consumer autosomal tests (AncestryDNA, 23andMe, MyHeritage) analyze hundreds of thousands of markers simultaneously, making them highly reliable.

The Reality

DNA testing is genuinely one of the most reliable tools available to identify biological relationships. When results seem surprising, the DNA is almost always correct, but the interpretation can be complex. That's exactly what our Search Angels do every day: help people understand what their results actually mean for their specific situation.

Common DNA scenarios

What surprising results often mean

My ethnicity results aren't what I expected
Ethnicity estimates are educated guesses based on comparing your DNA to reference populations. They get updated periodically as testing companies refine their algorithms. Small percentages (under 5 percent) are especially unreliable. Ethnicity surprises rarely indicate anything other than the imprecision of the estimate itself.
I have a close DNA match I don't recognize
An unexpected close match (sharing more than 200 centimorgans of DNA) almost always indicates a real biological relationship. This could mean an unknown half-sibling, a misattributed parentage, or a family secret going back generations. Our Search Angels specialize in interpreting these matches and figuring out exactly how you're related.
My DNA doesn't match a sibling or parent
If you and a full sibling share less DNA than expected (typically under 2,000 cM for full siblings), you may actually be half-siblings. If your DNA doesn't match a parent at all on autosomal testing, you are not biologically related to that parent. These results are rarely wrong, and we can help you understand what to do with that information.
I have no close matches at all
This can happen when you have ancestry from populations underrepresented in consumer DNA databases. Testing with multiple companies (AncestryDNA, 23andMe, MyHeritage) and uploading to free databases like GEDmatch and FTDNA can significantly increase your match count. Patience also helps as databases grow.
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If you're ready to look for biological family, not just understand your DNA results, our Request Help form is the place to start.

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