8 Mistakes People Make Using MyHeritage DNA (And How to Fix Them)

Devon Noel Lee
May 12
9 min read

Updated: May 20

So... you tested with MyHeritage DNA—or maybe you transferred your results to MyHeritage from another company. AWESOME!

However, are you reviewing your match list and thinking it makes no sense, or have you made a mess of things?

MyHeritage has some AMAZINGLY powerful DNA tools—Chromosome Browser, AutoClusters, and Theories of Family Relativity. But most people never look past the ethnicity results. And even the ones who do? They’re making critical mistakes that lead to junk matches, false trees, and wasted time chasing the wrong ancestors.

Today, we’re diving into the biggest DNA mistakes I observe people make on MyHeritage—and exactly how to avoid them. If you’ve tested, transferred, or are even thinking about it, this video could save you hours of frustration and a whole lot of confusion.

Mistake 1: Trusting DNA Matches Uncritically

And here it is—the silent killer of accurate family trees: blind trust in DNA matches. MyHeritage gives you a list of genetic cousins, and it feels like you’ve just been handed a map to your ancestors. But here’s the problem… some of those map points are just doodles.

Why? Because MyHeritage uses imputation—a techy word that basically means “we filled in the blanks between your actual DNA.” It helps standardize results across different testing companies, but it’s also how false matches sneak in. Some studies show up to a third of small matches could be garbage.

If your eyes just flicked to a 12 cM match and thought, “But she has Grandma’s eyes!”—slow your roll. Segments under 15 cM are way more likely to be false positives. That’s not a cousin. That’s a coincidence.

Here’s how to fix it:

Prioritize matches that share larger segments—think 20 cM or more. And don’t just stay inside the MyHeritage bubble. Cross-check those matches on other platforms like FamilyTreeDNA or GEDmatch. If that segment is real, you’ll see it more than once.

Also, can we normalize ignoring matches under 10 cM unless we’re desperate? Raise your hand if you’ve ever gone down a rabbit hole chasing someone who turned out to be your match by cosmic accident. Yeah. Same.

Mistake 2: Not Testing or Uploading Known Relatives

This one’s a game-changer, and it’s hiding in plain sight: not testing or uploading DNA from your known relatives. If you have a parent, aunt, uncle, or grandparent willing to spit in a tube or upload a file—and you haven’t made that happen—you’re leaving gold on the table.

Why? Because every generation closer to the common ancestor makes the DNA picture clearer. A match that’s 75 cM for you might be 180 cM for your mom. Suddenly, that hazy cousin mystery just solved itself. Plus, relatives can help confirm false positives—if a segment doesn’t show up in them, you know it’s fluff.

Now, for folks who were adopted or have unknown parentage, this isn’t a mistake—it’s just reality. You work with what you’ve got, and you’re already doing the hard thing.

The fix?

But if you know who your relatives are, and they’re alive and curious? Upload them. Test them. Even if it’s just one more person, it sharpens your matches, boosts AutoClusters, and makes Theories of Family Relativity™ way more accurate.

Mistake 3: Blind Use of AutoClusters & Theories of Family Relativity™

AutoClusters and Theories of Family Relativity™ are like the flashy power tools in the MyHeritage toolbox. But here’s the catch: if you fire them up without knowing how they work, you’re just as likely to drill into drywall as you are to find an ancestor.

Let’s start with AutoClusters. These don’t include your closest matches—MyHeritage caps them at about 350 cM, which leaves out siblings, parents, and even some first cousins. That means you should solve those higher matches first, especially since they provide the cleanest clues. What AutoClusters do well is show how your more distant matches group together—often revealing shared surnames, locations, or ancestral lines.

But here’s the warning label nobody reads: if you have endogamy or pedigree collapse in your tree (looking at you, Acadian, Jewish, or Appalachian researchers), these clusters can be a tangled mess. So take them seriously—but don’t take them literally. Use them to spot patterns, then verify with paper and logic. If you’ve ever opened an AutoCluster and thought, “Why is everyone related to everyone?”—yeah, that’s endogamy waving at you.

Now for Theories of Family Relativity™. Unlike Ancestry’s ThruLines, these don’t just connect you through user trees—they MAY pull from actual historical records to bridge the gaps. That means they can help reconstruct lines where the trees drop off. But remember: the theory is only as good as the data it’s built on. If the source tree has Grandma marrying her brother and census records for a different state? You’re in fantasy land.

So, the fix here?

One, build out your biological tree on MyHeritage with quality sourcing. The better your tree, the better the algorithm performs. Two, always vet any theory against original documents, not just profiles. And three, use AutoClusters to support conclusions you’ve already started to suspect—not to invent ones you want to be true.

If you’ve made it this far and you’re nodding along, tap that like button so the algorithm knows you’re here for the smart takes—not the sloppy shortcuts.

Mistake 4: Not Using the Chromosome Browser

This right here is the tool that separates MyHeritage from Ancestry—and yet most people ignore it. If you’re only using ethnicity results and match lists, you’re skipping the actual genetic proof that can confirm or crush your tree theories.

The Chromosome Browser shows you exactly where you match someone—down to the segment. And here’s why that matters: just because you and your match share 45 cM doesn’t mean that 45 cM is useful. But when you find a long, clean segment on a single chromosome? That’s gold. Especially when multiple people from the same branch all match you on that exact same spot. That’s triangulation. That’s real evidence.

Ancestry doesn’t offer this. Not even a peek. MyHeritage does—and that means if you’re serious about using DNA for genealogy, this browser isn’t optional. It’s essential.

So what’s the fix?

Use the dang thing. If you have two matches you think might be related to the same ancestor, check the chromosome browser to confirm if they share a common segment with you. If they don’t? That theory needs work. If they do? You’re on the right trail. It’s the DNA equivalent of “pics or it didn’t happen.”

MyHeritage Chromosome Browser not showing triangulation — Be careful, on Chromosome 2, this is not triangulation.

Mistake 5: Using the Chromosome Browser Incorrectly

So, you found the chromosome browser. Congratulations. But if you're just eyeballing colorful bars and nodding sagely, we need to talk.

Here’s the problem: people use the browser like a shiny toy instead of a verification tool. They find shared DNA sections with a match and think, “Cool, we must be cousins,” without checking whether other matches overlap that same segment. That’s not how triangulation works. You don’t just need two people who match you—you need them to also match each other on the same segment. Otherwise, that shared DNA might come from two totally different ancestors. Or worse, be a coincidence. Thanks, endogamy.

Also? MyHeritage highlights shared segments down to 6 cM, which is generous—but dangerous. Segments under 15 cM have a high chance of being junk matches, especially with imputed data. So don’t become giddy over tiny overlaps. Prioritize matches with long, uninterrupted segments—ideally 15 cM or more. That’s where you find solid genealogical clues.

The fix?

Use the chromosome tool and select multiple matches to build out triangulated clusters. If two matches share the same 25 cM segment with you and each other, now you're cooking. That’s your genetic breadcrumb trail to a common ancestor.

Mistake 6: Not Recording Notes

Okay, tell me if this sounds familiar: you find a match, you poke around their tree, your excitement increases ... and then a week later, you completely forget what you figured out. Because you didn’t write it down. You didn’t label the match. You didn’t group it. And now it’s déjà vu in your DNA match list.

The mistake? Treating your DNA match list like a to-do list instead of a research log.

MyHeritage gives you actual tools to stay organized—custom labels, notes, and shared match filters. So use them. Create labels like “Dad’s side – German,” “Possible Smith Line,” or even “High cM but no tree (yet).” Color-code if you must. Leave yourself breadcrumbs so Future You doesn’t have to reinvent the family tree every dang time.

The fix:

Every time you work a match, tag it. Drop a note. Sort it into a cluster if you've identified a line. And if you're using a method like the Leeds Method or your own system for grouping by grandparent lines? Replicate that structure here.

Seriously, if you've ever solved a match and then lost it again, go ahead and hit the like button out of sheer frustration. You’ve earned it. Let's fix it and stop doing double work.

Now, these are all mistakes related to the matches themselves, but let’s look at related genetic tree-building mistakes that aren’t directly DNA related.

MyHeritage Family Tree View — How accurate is this tree?

Mistake 7: Overlooking Tree Quality

Let’s be honest—some of the trees on MyHeritage look like someone let a toddler smash the keyboard after watching one episode of Finding Your Roots. Names are wrong, dates are off, and somehow, a guy born in 1802 has a Facebook page.

The mistake? Trusting any tree that gets slapped onto a DNA match without checking the details. Just because MyHeritage shows you a Smart Match or a Theory of Family Relativity™ doesn’t mean it’s gospel. Trees are user-submitted. That means they’re only as accurate as the cousin who uploaded them—and let’s just say some cousins... shouldn’t have.

The fix is twofold.

First, review their tree.

Cross-check birthplaces, ages, and family groupings against records. If the tree says someone lived in Norway their whole life, but their supposed child was born in Missouri, you have a problem.

Second, build out your own tree on MyHeritage.

Don’t upload a copy-paste tree from Ancestry member trees. You want to build a source-based tree. You can build your tree on MyHeritage or import it from Ancestry and other locations. But again, base the tree on documentation as much as possible. Some cultures lack documentation and rely on oral history, and I acknowledge that you may have a different pedigree. However, for most of the genetic genealogy testing world, you should have at least one quality source for every name in your tree.

The more accurate data you give the MyHeritage, the better the Theories of Family Relativity will be. MyHeritage often builds its theories using both trees and records. That’s a massive advantage over Ancestry’s ThruLines, which only rely on member-submitted trees. But if your tree is blank, or your cousin’s tree is a trainwreck, MyHeritage’s theory will be too.

So if you’ve been ignoring your match’s tree—or worse, blindly copying it—stop. It’s okay. We’ve all done it. But let’s do better from now on.

This final mistake is believing that one genetic genealogy company will give you all the answers you need.

Mistake 8: Not Cross-Referencing Your Matches Across Platforms

Look, I get it. You test at MyHeritage, your matches populate, and you start sleuthing. But if you're not cross-checking those matches on other platforms like Ancestry, FamilyTreeDNA, or GEDmatch, you're solving a jigsaw puzzle without all the pieces.

The mistake?

Assuming a DNA match only exists where you tested. Many serious genealogists have their DNA spread across multiple platforms. And since MyHeritage has a large international user base, some of your American matches may only appear on Ancestry. Meanwhile, your Eastern European ones might be hidden on FamilyTreeDNA.

The fix:

Upload your raw DNA to other sites.

Another advantage that MyHeritage has over Ancestry is that it accepts uploads from other genetic genealogy companies. And, you can download your DNA and upload it to FamilyTreeDNA, LivingDNA, and GEDmatch. If you have completed this step, please type' Gold Star' into the comments so I know who the gold star students are. If you haven’t, no worries, go do that step and come back and let me know you’ve completed it.

Now, here’s the next challenge. If your DNA match has also tested elsewhere (particularly if they’ve tested on Ancestry or 23andMe, invite, persuade, or bully (just kidding) them to transfer their DNA to MyHeritage. Even if they don’t use MyHeritage, you can compare results with the amazing MyHeritage tools, which means you’ll receive better research that will benefit them in the long run. Plus, it costs them next to nothing, or it’s free if you’re willing to pay for their upload.

If you or your DNA match is not currently listed on MyHeritage and you remain uncertain, here’s the key point. A match that seems unclear on Ancestry often becomes clear on MyHeritage. You might not have a shared tree on Ancestry, but you do on MyHeritage (or the tools on MyHeritage help you visualize your relationships). Alternatively, a GEDmatch one-to-many report may reveal a triangulated group that includes your cousin from MyHeritage.

So, put your DNA test results everywhere, leveraging data uploads to reduce costs.

DNA strand with the title Free Guide Answers to the Most Common DNA Questions asked by new genealogists

Stop Making Mistakes with Your MyHeritage DNA Test Results

So there you have it—nine of the sneakiest, family tree-wrecking mistakes people make on MyHeritage, and more importantly, how to avoid them.

If you’ve been doing any of these… welcome to the club. Nobody starts as an expert, but the faster you stop trusting invalid matches, skipping segment data, or treating Smart Matches like gospel, the faster you’ll start building a tree that actually means something.

And if you’ve made it this far? You’re clearly serious about doing this right. So take a second to subscribe—I have more videos coming that’ll help you get the most out of your DNA tests without losing your mind. Or your ancestors.