Posted by Ancestry Team on February 7, 2017 in AncestryDNA, TechRoots

What if from your DNA, you could find out that you’re not just Irish, but related to the Ulster Irish who migrated in droves to the U.S.? Or descended from a group of African Americans in Maryland who left rural areas to put roots in cities. Or maybe the Acadians, who brought the French language and culture to Louisiana. What if you could see the people, places and migration paths in your family story?

Genetics has long been used to understand human history and migrations. However, due to limited samples or methods used, very few of these methods have shed insight into more recent human history over the last several hundred years.

After years of hard work, and a lot of rigorous statistics, we developed a novel scientific methodology that looks at how specific groups of people are connected through their DNA, what places they called home, and which migration paths they followed to get there – allowing genetics to reveal the history in a more recent time period than ever before.

Today, the science team is thrilled to announce that our work on identifying finer grain population structure was published in Nature Communications, “Clustering of 770 thousand genomes reveals post-colonial population structure of North America.”

The new research leverages the powerful combination of family history and genetic data unique to Ancestry to surface a more concrete and detailed genetic portrait of how our recent ancestors responded together to historic forces like politics, famine, war and immigration.

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Caption: Figure 3 | Distribution of ancestral birth locations in North America associated with IBD clusters. Points show pedigree birth locations that are disproportionately assigned to each cluster. Only birth locations with OR > x within indicated generations y–z are plotted, in which parameters x, y, z are chosen separately per cluster to better visualize the cluster’s historical geographic concentration; full distributions of ancestral birth locations in the US, Europe and worldwide are given in Supplementary Figs. 18–20. For each cluster, points are independently scaled by the number of pedigree annotations. See Fig. 2 and Table 1 for more details. Note that clusters are separated into two maps only for clarity. Also note that the concentration of Puerto Rican ancestors in Hawaii probably reflects their arrival there in the early 1900s65.

 

How does the science work?

We first created a network of genetically-identified relationships — based on DNA alone — among over 700,000 individuals who consented to research.  Using network analysis techniques, we identified clusters of individuals in the network: groups of individuals who are slightly more related to one another than to individuals outside their cluster. In other words, from genetic data we identified novel “population structure” – subtly different groups of individuals within a larger population.

Having such a large genetic dataset allowed us to uncover these clusters, or communities, that would have not otherwise been possible.

We then added context to these clusters of genetic communities with family tree data to understand the origins of these groups of people, and to uncover the groups’ migration patterns and ancestries. From this we uncovered, in great detail, the historical explanations for the patterns observed in the genetics.

For example, certain groups of individuals corresponded to descendants of Scandinavian or French Canadian immigrants to North America, and we even identified groups of descendants of settlers such as the individuals with ancestry in the Appalachians and in New Mexico who experienced geographic or cultural isolation within the US. The data also depicted movements and settlements across east-west and north-south gradients within the United States – and remarkably matches known history.

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Caption: Figure 4 | Genealogical data by generation trace migration of French Canadians (magenta) to the US and origins of Cajuns/Acadians in Atlantic Canada (blue). Map locations are plotted if OR > 10 within the indicated range of pedigree generations (date ranges give the 5th and 95th percentiles of birth year annotations). Points are scaled by number of pedigree annotations, separately for each of the 6 maps. Note that not all current political borders are shown. See Fig. 2 for more details.

 

What does this research mean for me?

This research has exciting implications for current and potential future customers of AncestryDNA. Recall that this research identified clusters, or genetic communities, of individuals, as well as their histories – where their ancestors may have lived, where they migrated to and from, what were their last names, and more. Inversely, that means that we can identify the genetic communities that an AncestryDNA customer belongs to. That in turn means that we can use an individual’s DNA to provide them with an extremely detailed historical portrait of the lives of some of their recent ancestors – more recent than previously possible. For example, we could tell someone where some of their ancestors might have lived and moved throughout their life, as well as potential historical reasons for those migrations, during the last several hundred years.

This work was made possible by the contributions thousands of customers who have researched their family trees, taken the DNA test, and agreed to participate in scientific research. In the coming months, we’re excited to share these findings with each of you in a personalized experience.

27 Comments

  1. Brian Podoll

    While this map shows a couple specific ethnic identifications in the Upper Midwest, such as Scandinavians and Finnish, the largest settlement group across the entire Midwest and largest pre-1920 immigration group, Germans, are not identified at all. Furthermore, it remains to be seen whether there is enough of a DNA database or of willing participants, but very different groups from specific historic regions of Germany could be identified by their migrations. As one example, there could be a large swath of settlement from the northwestern counties of Indiana, most of east central Wisconsin, central and southern Minnesota, as well as eastern portions of both Dakotas of Prussians who came from the Netze River Valley region at the confluence of the former provinces of Posen, West Prussia, Pomerania, and Brandenburg. The DNA identification of these people would likely be complex, because many reflected ancient admixtures of Teutonic and Slavic elements and in some cases, even earlier Baltic influences. These were reflected in their surnames alone, much less their specific places of origin. Other such examples would be East Frisian people from northwestern Germany, whose migrations went from northern Illinois into east central Iowa and certain parts of southern Minnesota and South Dakota. Likewise with North Frisian people from Schleswig in northernmost Germany, who made specific settlements in easternmost and northwestern Iowa. At this stage, their DNA is likely to say little more than “Europe West.” Those are but a few German-specific examples, but could be applied to other ethnic groups across the Midwest, especially to farming people who relocated to terrains similar to their European homelands.

  2. Lori Hansen

    In addition to the lack of German data, there is also a lack of Jewish ancestry data. Instead of trying to Define Jewish populations by country of origin, it makes sense to identify them as a group that settled primarily in Manhattan and Cincinnati, Ohio.

  3. Patti

    Brian Podall is correct. With over 25 million descendants of German born ancestors recorded in 2008, they make up the largest ethnic group of immigrants in the United States.

  4. Patti

    I agree with Brian Podall. The largest ethnic group – German immigrants – is missing. Over 25 million descendants of German born immigrants are in the US today. These immigrants escaped fascist Germany. Many fought in the civil War and world wars against fascism and slavery.

  5. Tobias Kemper

    The Germans as largest group of immigrants came in the 18th and most in the 19th century. They did not escape fascist Germany 1933-45.

  6. Anita Richards

    i recieved my dna i can see the history in it but in no way did it refure to my family in the least my family came from paris to migrate to Canada nothing was mention i was looking for

  7. Annette Crawford

    Am always interested to see where “settlements” of various ethnic groups. Since beginning to research my family on both sides, I have traced my maternal grandfather from Finland to Florida. He went back to Ellis Island 6 years later to pick up my grandmother and their 7 year old son. Instead of going back to Florida, they went to South Carolina. The family moved through lower SC and appears to have set down roots there. Unfortunately both were deceased by 1938. My uncle was left to care for 2 sisters and 1 brother. Now working on finding out their history in Finland. I have made contact with a 3rd to 4th cousin on my grandfather’s side. She is helping me locate other family members. It is still a mystery as to why he went to Florida. I do have his ship’s listing that listed he was meeting up with an individual who appears to be Swedish. I am still in the dark when it comes to my grandmother’s side. The parish has given me some data, but there is more to learn. Taking the DNA test has opened some possibilities.

  8. Al Doyne

    I want to ditto Brian’s comment above and anxiously await similar maps showing German migrations especially to the Midwest; and then there’s the Irish.

  9. Tom McCorkill

    Wow! What a wonderful advance. I can rememb3er my genetics course in college when I knowledge was limited to the eight pairs of chromosomes then identified. Why are people so critical at this point as there is surely much more to come.

  10. Pauline Pendlebury

    Thank you Ancestry.com This is wonderful..and it will be exciting to see what the future advances bring also in relation to other countries etc. Great work !! 🙂

  11. Ryan Springer

    “In coming months” is the worst part as I hate waiting. My best guess would be around DNA day, but coming months never mean soon so we will see.

  12. Daniel Hester

    Nothing against Acadians, but they migrated to Louisiana more than 60 years after the French culture and language had arrived at the Gulf Coast. I wonder if my French Creole IBD groups are lumped in with the Acadians, even though I have no Acadian ancestry.

  13. Cindy Brady

    I think it is a little premature to get out underwear in knots over any particular Ethnic groups being left out. I don’t see the Irish or Chinese singled out either. What I do note is the stark difference a river makes. Early migration depended on the waterways, and without those waterways, groups seemed to be far more isolated. The other thing I am VERY interested in knowing is how the validity of the 700,000 family trees was tested. I LOVE the East/West route linking UTAH. It only serves to highlight both the blessing and the curse we all deal with in the LDS’s focus on family history. Thank you, LDS for all of the research and preservation of records worldwide. However, we are all only human and there is a multitude of bogus family trees in the LDS data bases, and all of our have errors, “mirror tree,” family legends, franken grafts, and downright fakes. If that was allowed into the 700,000, what did you use for your merging of error? I have 40 years of researching my family – building and correcting, adding on to what what left by prior generations. I am very confident on some branches, and those Mayflower, DAR, SAR and Salem connections are all verified and State pioneer certificates abound to validate our family’s East-West journey. I could have told Ancestry that without the DNA and the map. I even have the journals of the river journeys. All that said, it is interesting research and it will be very interesting to see where it leads – it is the unverified family tree information that is the weakest part.

  14. LeVaJe

    Most if not all of the concerns in these comments are covered in the actual study. There are even additional images with info on European Jewish, Irish, African American, and others. Hopefully they will update the ethnicity estimate maps with this information.

  15. Lisa Coan (Anderson)

    This is really interesting!! I can’t wait for more information–super exciting development. I see it now as a work in progress, with much to look forward to.

  16. Donald

    Hopefully those 700,000 people have well researched trees and not those ones based in fantasy. Also I am still waiting on the update that Ethnicity was supposed to go through. Is it ever coming? I tell you FTDNA and Ancestry are both lagging behind on the DNA scene lately.

  17. Larry Morin

    In spite of some of the negative comments, I look forward to seeing your findings. Progress is progress. As a French Canadian descendant (both maternal and fraternal), of those I could, I’ve mapped all my documented ancestor birthplaces in France. It’s interesting to see where in France they started from, e.g., Brittany.

  18. Hasani Carter

    Thank you for doing this! I hope this helps me with tracking my enslaved Ancestors. Possibly back to their African homes

  19. walimpet

    What a fascinating study! Thank you for sharing it with us. It’s exciting to be part of your groundbreaking DNA research. Keep up the great work and keep on sharing!

  20. Elistariel

    Maybe this will one day help me learn more about my German immigrant ancestor who first appeared in the middle of South Carolina in 1852 from Baden-Baden.

  21. mary

    This is good news. However, with the new batch of “Christmas gift” DNA tests coming on line, I have a bigger problem than ever. Ancestry has provided us with massive amounts of data and no way to manage the data. A star is practically useless when faced with thousands of DNA matches on multiple test results. I would really like to see some folders, color coding, or anything useful to at least triage the data into manageable segments.

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