MyHeritage Breakthrough: The Theory of Family Relativity™

MyHeritage made an announcement this morning at RootsTech2019 that should interest every genealogist who has had a DNA test. I had a chance to use this new innovation briefly and it confirmed a “maybe” entry in my personal genealogy database that had bugged me for years. I previously had found a mention of a man that I suspected is my great-great-grandfather, along with information about his parents. However, the brief mention was in someone else’s family tree and I wasn’t confident about it’s accuracy.

The new Theory of Family Relativity™ not only found him but also showed the amount of DNA that he and and I and another of his descendants share. It also displayed information about a lot of distant cousins of mine that I previously was unaware of. Not bad for the first five minutes of use!

Here is the announcement from MyHeritage:

TEL AVIV, Israel & LEHI, Utah–MyHeritage, the leading global service for family history and DNA testing, revealed today its latest innovation in genetic genealogy — the Theory of Family Relativity™. This technology offers users, for the first time ever, theories that utilize nearly 10 billion historical records and family tree profiles to explain DNA connections. Until now, family history enthusiasts used two distinct domains for making discoveries: the paper-trail world of records and trees, and the biological world of DNA connections. Now, MyHeritage has combined these two domains and integrated them seamlessly.

The Theory of Family Relativity™ is based on a big data graph that connects billions of data points drawn from thousands of databases on MyHeritage, in real time. Every node on this graph represents a person, and every edge depicts a blood relationship between two individuals that is described in a family tree or a historical record; or a match between two tree profiles that are likely to be the same person; or two records that are likely to be about the same person. These connections between people and records are established by MyHeritage’s industry-leading matching technologies. MyHeritage engineers and algorithm experts led by the company’s CTO, Sagi Bashari, developed a unique approach that allows the big data graph to instantly compute all paths between millions of blood relatives. The Theory of Family Relativity™ draws upon this resource to construct the most plausible theories explaining how pairs of people linked by a DNA Match on MyHeritage are related, using family trees and historical records.

Previously, users who took a DNA test looking to find relatives were faced with puzzling lists of thousands of distant relatives, without many clues explaining the DNA connections. Now, for a growing percentage of these DNA Matches, theories are provided by MyHeritage that explain the precise relationship paths using trees and records. In these theories, not only does genealogy illuminate DNA connections, but DNA also helps separate fact from fiction in the genealogy and shows which tree and record connections appear to be correct.

This technology uses millions of family trees on MyHeritage, as well as the World Family Tree on Geni, which is replicated daily to MyHeritage, and the single family tree of FamilySearch, which is also replicated daily to MyHeritage under license. This combination results in the most comprehensive family tree traversal available today. Additionally, the technology utilizes billions of historical records on MyHeritage, including all census records, as well as the MyHeritage Record Detective™ technology that indicates whenever two records are about the same person. For example: a theory that explains a DNA Match between two users can begin in the family tree of the first user, traverse through a series of matching trees into a census record, continue to a household relative, who then matches into another tree, until the path completes with the family tree of the second user. MyHeritage displays the complete path of every theory, and explains every step along the way, allowing the user to verify its accuracy. Each theory is presented with a confidence level that is based on the confidence of the matches used to construct it.

“Our new technology is a game changer in its scope and power and is a tribute to our passion for developing the best genetic genealogy tools for our users,” said Gilad Japhet, Founder and CEO of MyHeritage. “Using genealogy to explain DNA Matches, and using DNA to validate genealogy matches, combines the best of both worlds. We expect this technology to help people make new discoveries in their family history. With every day that goes by, this technology grows even more powerful as more tree profiles, historical records and DNA kits are added to our global database.”

The Theory of Family Relativity™ feature is included for free with all Premium, PremiumPlus, and Complete subscriptions on MyHeritage. Individuals who upload their raw DNA data from other testing services to MyHeritage who do not have a subscription can pay a one-time fee of $29 per DNA kit to unlock the Theory of Family Relativity™ and the full range of advanced DNA features offered by MyHeritage.

To purchase a MyHeritage DNA kit, visit

About MyHeritage

MyHeritage is the leading global service for family history and DNA testing. As technology thought leaders, MyHeritage has transformed family history into an activity that is accessible and instantly rewarding. Its global user community enjoys access to a massive library of historical records, the most internationally diverse collection of family trees, and groundbreaking search and matching technologies. Launched in November 2016, MyHeritage DNA is a technologically advanced, affordable DNA test that reveals ethnic origins and previously unknown relatives. Trusted by millions of families, MyHeritage provides an easy way to find new family members, discover ethnic origins, and to treasure family stories, past and present, for generations to come. MyHeritage is available in 42 languages.


I am somewhat suspicious of this private company and its recent emergence as a self-proclaimed leader is various fields. Their website tells me they are using facial recognition to match up people who have submitted photos. Is this part of their new trade marked process?


    —> Is this part of their new trade marked process?

    No. MyHeritage uses facial recognition technology only when you tell it to. It compares any picture you specify against any other picture(s) you specify to see if the software can find similar physical characteristics in the pictures. Nothing else.


Where does one find this “Theory of Family Relativity” option on their site in order to use it? Thanks..


    As stated above, this theory of relativity is available only to those with paid (complete, premium and premium plus) subscriptions to My Heritage and is not available to those with free accounts. It will show up in the DNA matches for those for whom there is a theory connection. For close relatives, 1st and 2nd cousins for whom there are good family trees, the theory works fine. For anyone who is of 3rd cousin or highfurther out, the theory makes some pretty crap connections. These connections are only as good as the users who added them to their tree, and let me tell you, some of my connections cannot be my relatives because their trees just do not make sense. The Theory seems only to latch on to similar names no matter where they came from or when they were born and died.


I agree, WHERE IS IT. I searched all over and can’t find it, I’m a Complete subscriber, with a submitted DNA test results uploaded.


I just went to MyHeritage, clicked on the top for DNA and the first thing on the page was Theory of Family Relativity. I just watched RootsTech about this new feature, not sure I would trust it, just like Ancestry’s shaky leaves are hints.


Searched for “Theory of Family Relativity” at My heritage, Response: No results… Please try a different phrasing


If the theory has found connections between you and other people, then these will show up in your DNA matches. If there are no connections – because the family trees just don’t match – then there are no connections. This entire theory hinges on users at both ends and in between, all having ACCURATE trees. Judging by what I have seen in the few theory connections that I have, there are very INACCURATE trees on My Heritage!!!!


    Nigel Huffingway Smythe February 28, 2019 at 1:56 am

    The “theory” program itself also makes some horrible guesses (equating two people in different trees that are in fact different people) that can’t be blamed on bad data.

    That said, “theory” came up with 2 hints that were absolutely correct and 2 hints that were off-the-wall impossible. So it’s useful as a hint, but certainly not as the final word.


    —> So it’s useful as a hint, but certainly not as the final word.

    Absolutely! That is true of every computerized matching service and doubly true when humans try to find matches amongst the family trees uploaded by other humans. Never, ever believe any claims (human- or machine-generated) until you verify the information yourself using the various sources that genealogists have been using for decades.

    Everything you read online on ALL web sites needs to be treated as POSSIBILITIES, not as facts.

    Experienced genealogists already know the need for verification of every claim. However, newcomers need to learn the lessons from the more experienced genealogists.


    I have uploaded some of my first cousins DNA to my tree. Two of them show theory of Family Relativity matches. Their matches are also matches to me but I have no theory of family relativity matches.
    I don’t understand why


    —> but I have no theory of family relativity matches. I don’t understand why.

    The most obvious reason is that none of your relatives have uploaded THEIR DNA information. That’s true on my father’s side of the family. While I have uploaded my DNA info to MyHeritage, I rarely get matches on my father’s side. When I do, they are usually for very distant relatives, such as 5th cousin or even more distant.

    In contrast, I am flooded with matches to my mother’s side of the family. Her ancestry is 100% French-Canadians and those families all lived for a couple of centuries in somewhat isolated areas where families kept intermarrying into the same other nearby families. All French-Canadians seem to be related to each other and quite a few of today’s French-Canadian descendants have uploaded their DNA info to MyHeritage. I have more than 2,000 possible DNA matches to my mother’s family tree waiting for me to prove or disprove the matches. When I get the time… yeah, sure… In contrast, I have almost zero DNA matches to my father’s (Yankee) family tree.

    I am not saying that is the only reason for a lack of DNA matches but it may be the most common cause.


In early versions My Heritage thinks I am my mother, and does not protect privacy of children by blocking “living people”. Beware!


There are lots of trees, but they are only as good as the researcher is in finding the proof of the connection. Some searchers are simply name grabbers to build their tree, not taking into consideration the areas the family has been for many years. They pick one that is off in a distant area but has the same name. Yes they may have migrated, but prove it before you add it to your tree. So many people copy other listed trees full of obvious errors and then wonder why they can’t locate their true ancestor. Some post a child’s birth way BEFORE the parents were born. Please check your entries before posting them. I recently had an interesting find via DNA of a connection to a family I had wondered about for years that lived in in area where gr grandparents lived. Only problem in facts is that they have no child listed to match my ancestors birth date & name. Yet DNA says we match. No Tree lists my direct ancestor. Similar names but not date. The father’s name is correct. I did not know what the mothers name was. The search continues before I add them to my tree.


With all of the many erroneous family tress on these websites, I hate to imagine the hash that will be created when they are all linked with DNA thrown in. A major participant in this will not even put a non-subscriber in contact with a subscriber so that the non-subscriber can provide the correct lineage to the individual. In one case two people have removed my ancestor from his ancestors and siblings and substituted their own ancestor (of same name). One person has the faulty tree on at least three sites and another person clobbered into that tree with their own line creating a great mishmash of what should be three distinct families. Apparently some people don’t care if their tree is incorrect, but I think the providers of the sites should give some thought to the disservice they are doing to serious researchers by failing to vet the trees, to require sources other than a web site or conglomerated web tree, and enable outsiders to contact with corrections. I’ve done three generations of research further back on the other person’s real line, a perfectly honorable and sound line, and have absolute proof on it. I would have been happy to supply it for free to have the corrections made to the various web sites.


    I have a few comments:

    Not all the various genealogy web sites operate in the same manner. For instance, on MyHeritage NOBODY can ever replace or change your records that you entered. If you upload any family tree information to MyHeritage, your information remains there forever and ever with no changes, unless YOU later change it. Nobody else can change anything you uploaded. Some other web site operate differently.

    2. MyHeritage’s new Theory of Family Relativity looks at your family tree data that you uploaded PLUS other family trees that other people uploaded PLUS original records obtained from birth, marriage, and death records PLUS old newspapers PLUS probably more items that I cannot remember at the moment. The intent is to analyze ALL available sources of family tree information, not just the (questionable) family trees uploaded by other people.

    3. Non-subscribers to MyHeritage CAN upload their DNA information and still see the resultant matches although there is a small fee for that. I think it is $29 US but I am going from memory. I might be wrong on the exact amount.

    4. The Theory of Family Relativity is called a THEORY for a very good reason. It is designed to supply theories, not proven facts. The online documentation stresses this very clearly. In the old days (such as last week) finding matching DNA centiMorgans was a very labor-intensive process. Most people who did that spent hours loading information into spreadsheets or some similar process and then MANUALLY scanned hundreds, perhaps thousands, of entries looking for matches. Even then, it was no proof of a relationship. Instead, it showed you possible or theoretical relationships. You still had to revert to old-fashioned and well-proven genealogy techniques to prove a relationship.

    The new Theory of Family Relativity does exactly the same thing. It takes out the gruntwork: the labor intensive manual comparisons. In return, it shows you all the possible or theoretical relationships. As always, you then have to revert to old-fashioned genealogy methods to prove or disprove a possible relationship. In other words, it requires human judgement. None of today’s computers will ever return 100% accuracy all the time. That is true of MyHeritage as well as all the other online DNA web sites. The only thing different is that the manual gruntwork is done for you within minutes and it delivers essentially the same results that could have done manually last week or last year: a list of THEORETICAL or POTENTIAL matches. Then you have to take over from there to find the matches that are correct.

    Other web sites may or may not do the same.


    I tried the new Theory of Family Relativity tool on MyHeritage and in about one minute found a connection to one of my matches that we had been trying to figure out for over a year of searching through documents and family trees and trying to build out our own trees along multiple lines. It was like trying to read a map in the dark without a flashlight. Now we have our own yellow brick road helping us to put together a targeted research plan instead of wandering around the wilderness trying to figure out where to look.


    Just noticed that after clicking on the link to review one of the Theory of Family Relativity entries, there is now a confidence rating right at the top of each theory (in very small print, so it’s easy to miss). The confidence rating for a suggested relationship to known 2d cousin was 92%. The more distant relationship mentioned in my earlier post was rated at 42%. The suggested most recent common ancestral couple in that case lived around about 200 years ago and had at least a dozen known children, so you can see why we were having so much difficulty picking out the most likely path to start researching first.


First, I did not mean that someone had changed my tree on a website. I haven’t put one on any site, but relatives have and I’ve seen what has happened to them. In the incident I was referring to, a person did incomplete research, found my ancestors and assumed they were hers. She put the tree on at least three sites. A second person then found the tree and linked their ancestor of the same name, then created a family with children of all three different families!
Second, I was not asking to change the person’s site myself. I asked to be put in touch with the tree owner in some way that did not invade their privacy so that I could provide them with the correct information (at least three generations worth with documentation from original sources). MyHeritage refused to do this.
Third, a first cousin took the Y-DNA test sponsored by a “one-name” web site in hopes of helping me establish additional generations of our great-great-great grandfather’s line. The results were about 30 first or second level “matches”, all with different surnames. Even with some extra-marital events on all sides, that seems like a stretch, especially since I have solid documentation on our line. As a result I am somewhat skeptical of DNA results and prefer to find documentation to prove ancestors and relatives. It will be interesting to see what this Theory of Relativity does to the family I described above in the first tree, since none of the offspring shown are related to the parents.


I’ve only had one “Theory” match show up so far, an it’s a disaster. It plots my ancestral line back four or five generations to my most distant ancestor (born circa 1800 in Lincolnsshie, England), then makes a direct match with someone with the same first and last names as my ancestor, but with an additional middle name, born somewhere in the Wild West of America in 1801!
I’m reserving judgement. That being said, I AM impressed with their AutoClustering, though.


    Again, these are THEORIES, not proven facts. They all still require old-fashioned genealogy research to prove or disprove the theories. The person who shares DNA centiMorgans with you undoubtedly is a relative but might be either a close or even a very distant relative. The more centiMorgans you and the other person share, the closer the relationship. If you share only a very few centiMorgans with the other person, you might be 4th or 5th or possibly even more distant cousins. (This is described in the accompanying documentation.)

    The old way of comparing centiMorgans required a lot of manual work with spreadsheets or something similar. Even then, the manual methods only provided POSSIBLE matches to relatives.

    The new Theory of Family Relativity™ removes the manual effort and replaces it with software to perform the same calculations as always.

    Again, the results always point to relatives because it points to someone who shares at least a bit of DNA with you. However, it might be very distant or very close. It is up to you to prove the connection. The new Theory of Family Relativity™ simply says: “start here first.”


I am a fully paid subscriber and have been for several years. I have a tree on My Heritage and I know there are others who have trees that match mine, and who have DNA that match me but I can’t find Theory of Family Relativity anywhere. Chromosome browser not very helpful. Auto cluster – I’m waiting for them to email the results. Not impressed.


The MyHeritage site has provided me with some very interesting documentary evidence about myfamily from obscure sources I probably would never have found out about elsewhere. That said, it seems to me that their search algorithms are a bit too loosey-goosey when it comes to sorting out what seem to be obvious false hits. I get way too many results suggesting matches to information about people of the same or similar names who lived in different centuries and in different countries thousands of miles apart. Wading through page after page after page of them to try and find the much smaller number of genuinely useful hints is very tiring, and it is easy to miss the few roses to be found amon the thorns. To the extent the Theory of Family Relativity is drawing upon the same algorithms, that might explain why some people are getting so many inaccurate suggestions. Would it help the algorithms to learn if those of us who are lucky enough to have a tree that is solidly documented from original primary sources made better use of the reject button when presented with such blatently obvious mismatch?


Leave a Reply

Name and email address are required. Your email address will not be published.

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <pre> <q cite=""> <s> <strike> <strong> 

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: