A new update to the 23andMe+ Premium™ Historical MatchesSM feature allows members to learn if they are genetically connected to Vikings massacred in the Kingdom of England on November 13th, 1002 CE. This historical event came to be known as the St. Brice’s Day Massacre because it occurred on the feast day of St. Brice, a French cleric who lived in the 5th Century and was later canonized.



<figure class="wp-block-image alignright size-medium"><img loading="lazy" decoding="async" width="178" height="300" src="http://35.88.189.111/wp-content/uploads/2024/11/Ethelred_the_Unready-178x300.jpg" alt="A medieval print of King Aethelred the Unready" class="wp-image-33487" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/11/Ethelred_the_Unready-178x300.jpg 178w, https://blogcms.23andme.com/wp-content/uploads/2024/11/Ethelred_the_Unready-606x1024.jpg 606w, https://blogcms.23andme.com/wp-content/uploads/2024/11/Ethelred_the_Unready-521x880.jpg 521w, https://blogcms.23andme.com/wp-content/uploads/2024/11/Ethelred_the_Unready-699x1180.jpg 699w, https://blogcms.23andme.com/wp-content/uploads/2024/11/Ethelred_the_Unready.jpg 710w" sizes="auto, (max-width: 178px) 100vw, 178px" /><figcaption class="wp-element-caption">King Aethelred the Unready</figcaption></figure>



It’s a grim connection to the past, but this new update adds to the more than 500 historical individuals in 23andMe’s innovative<a href="https://blog.23andme.com/articles/23andmes-historic-matches"> Historical Matches feature</a>.



These historical individuals are people who lived hundreds or thousands of years ago, including those killed on St. Brice’s Day from what is known as the Viking Age and individuals from ancient Rome, ancient China, or medieval Central Europe, to name a few. Some are known historical individuals like Beethoven, but most are nameless, like those killed over a thousand years ago on St. Brice’s Day.



<h2 class="wp-block-heading" id="h-how-historical-matches-are-made">How Historical Matches Are Made</h2>



<a href="https://blog.23andme.com/articles/23andmes-historic-matches">Historical Matches</a> identify places in your genome where you share identical DNA with ancient or historical individuals whose genomes have been sequenced, typically from archaeological studies.



For this latest update, the data comes from a 2020 study of the<a href="https://pubmed.ncbi.nlm.nih.gov/32939067/"> genomics of the Viking World</a>.



As part of that study, researchers sequenced the genomes of historical individuals buried in two mass graves in England—one in Oxford and one in Dorset—providing new insights into their ancestry. 23andMe scientists have added publicly available data from 27 of these historical individuals who were very likely killed during the St. Brice’s Day Massacre.&nbsp;



<h2 class="wp-block-heading" id="h-what-happened-on-st-brice-s-day">What Happened on St. Brice’s Day?</h2>



In the late 10th and early 11th centuries, the Kingdom of England faced relentless raids by Danish Vikings. Believing that the Danes were plotting to overthrow him, King Æthelred II of England, known as “Æthelred the Unready,” ordered a mass execution of all Danish settlers in his kingdom.&nbsp;



Historians do not know how many people were killed on that day, but among those reportedly killed was Gunnhild, the sister of Denmark’s King Sweyn Forkbeard, along with her husband. Enraged by the murder of his sister and brother-in-law, Sweyn intensified his raids on England, eventually seizing the English throne in 1013 CE and forcing Æthelred into exile. However, Sweyn’s rule of England was short-lived; he died just five weeks later due to unknown causes (some sources say that he fell from a horse, while others say that he was killed).&nbsp;



<h2 class="wp-block-heading" id="h-unearthing-the-past-through-archaeology">Unearthing the Past through Archaeology</h2>



 In 2008, excavations on the grounds of St. John’s College at Oxford University led to the discovery of a mass grave that contained the remains of 33 men and two teenage boys. The skeletal remains showed evidence of sharp-force trauma, with wounds often inflicted from behind, suggesting the victims were attempting to flee.



A year later, in 2009, another mass grave was discovered in Dorset England, that contained the remains of about 50 men. Similar to the Oxford site, the men died violently. In this case, all had been decapitated, with their bodies carelessly thrown into the burial pit and their heads piled together at the southern edge of the grave.&nbsp;



Although no historical records directly link either of these mass graves to the St. Brice’s Day Massacre, radiocarbon dating of the skeletal remains align with the date of this event. Further, the violent nature of the injuries the individuals sustained and the careless way in which they were buried are consistent with a massacre, offering further evidence of the brutal actions taken on that day.



<h2 class="wp-block-heading" id="h-learn-more">Learn More</h2>



If you are a 23andMe+ Premium member, you can check it out to learn more about the St. Brice’s Day Massacre and to find out if you are distantly related to the Danish Vikings who died on this day in history or to hundreds of other historical individuals.&nbsp;



 Not yet a member? Learn more about <a href="https://www.23andme.com/compare-dna-tests/">all that 23andMe+ offers here</a>.

A photo showing the archeological dig where the skeletal remains of Vikings believed to be killed in the St. Brice's Day Massacre in Oxford England.

23andMe Blog

23andMe Blog Team

Are you related to Vikings killed in the St. Brice’s Day Massacre?

Just in time for family gatherings this holiday season, 23andMe launched a new Records &amp; ArchivesSM feature that promises to make family tree building more accessible for its 23andMe+ Premium members customers.&nbsp;



<figure class="wp-block-image aligncenter size-large"><img loading="lazy" decoding="async" width="1024" height="576" src="http://35.88.189.111/wp-content/uploads/2024/10/How-to-build-image@2x-1-1024x576.jpg" alt="" class="wp-image-33470" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/How-to-build-image@2x-1-1024x576.jpg 1024w, https://blogcms.23andme.com/wp-content/uploads/2024/10/How-to-build-image@2x-1-300x169.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2024/10/How-to-build-image@2x-1-768x432.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2024/10/How-to-build-image@2x-1-880x495.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2024/10/How-to-build-image@2x-1-1180x664.jpg 1180w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /></figure>



<h2 class="wp-block-heading" id="h-new-branches-on-the-family-tree">New Branches on the Family Tree</h2>



This easy-to-use tool leverages census records from the United States, Canada, and the UK and death records from the US. Enter a relative’s name and birthdate, and Records &amp; Archives will search through historical documents to find a match and new information via ‘hints.’ While not yet a comprehensive records search, the new feature can help identify possible relatives in your family tree. We hope to add new functionality in the months ahead.



These hints may also uncover unknown family members, helping you create a fuller picture of your heritage.&nbsp;



The tool takes some of the work out of building a simple family tree. It can help those looking to add names, dates, and hometowns to their family tree and map out relationships along the branches of that tree.



With this new feature, users can go beyond genetic testing and learn more about relatives who never had the chance to submit DNA samples, enriching their family tree with new names, dates, and relationships.&nbsp;



<figure class="wp-block-image size-large"><img loading="lazy" decoding="async" width="803" height="1024" src="http://35.88.189.111/wp-content/uploads/2024/10/records_archives_01-803x1024.png" alt="" class="wp-image-33471" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01-803x1024.png 803w, https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01-235x300.png 235w, https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01-768x980.png 768w, https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01-690x880.png 690w, https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01-925x1180.png 925w, https://blogcms.23andme.com/wp-content/uploads/2024/10/records_archives_01.png 1537w" sizes="auto, (max-width: 803px) 100vw, 803px" /></figure>



The hints from 23andMe&#8217;s Records &amp; Archives help users fill in the gaps, uncover lost branches of their family history, and add depth to the information they&#8217;ve already gathered.



<h2 class="wp-block-heading" id="h-a-few-clicks-to-build-new-connections">A Few Clicks to Build New Connections</h2>



The new Records &amp; Archives feature makes genealogical research more accessible and efficient.



It&#8217;s a simple but powerful way for customers to go beyond their DNA relatives and fill out their family trees using historical records. With just a few clicks, 23andMe+ Premium customers can now discover long-lost connections, solve a puzzle in their family history, or deepen their understanding of their heritage.



<h2 class="wp-block-heading" id="h-find-out-more">Find out More</h2>



All customers can add to their Family Tree and see if there are record matches, but only 23andMe+ Premium customers in the United States, Canada, and the UK can see details of those record matches and save them to their tree.&nbsp;&nbsp;



23andMe Ancestry Service or Health + Ancestry Service customers can go <a href="https://you.23andme.com/chip-upgrade/">here to upgrade</a> to 23andMe+ Premium to use Records &amp; Archives.



Not yet a customer? Learn more about<a href="https://www.23andme.com/compare-dna-tests/"> all that 23andMe offers here</a>.

Records and Archives

Every October, we celebrate Italian-American Heritage Month, which honors the accomplishments of Italian immigrants and Italian-Americans, who comprise the fifth-largest ethnic group in the United States. In celebration, 23andMe+ Premium members, using the Historical MatchesSM feature, “Historical Matches,” can now discover how they are genetically connected to the ancient inhabitants of one of Italy’s most famous cities: Rome.



<h2 class="wp-block-heading" id="h-the-ancient-city-of-rome">The Ancient City of Rome</h2>



Rome was founded in the 8th century BCE. At the time, it was one of many independently governed city-states on the Italian Peninsula. By its peak, during the Imperial Period (27 BCE–476 CE), Rome had grown into a major cosmopolitan city with over one million inhabitants. It served as a center of commerce that linked people and goods from throughout the Mediterranean, the Near East, North Africa, and beyond.



The city of Rome served as the capital of the Roman Empire from its founding in 27 BCE until 330 CE when Emperor Constantine moved the capital to Byzantium (renaming it Constantinople in his honor). After losing its status as a capital city, Rome gradually lost its political prominence and experienced a dramatic decline in population size. Following the fall of the Western Roman Empire in the 5th century CE, Rome’s population fell to less than 100,000 people. It wasn’t until around the 14th century CE that the population size began to increase again.&nbsp;



Despite its fluctuating political status, Rome endures as a cultural and religious center to the present day.



<h2 class="wp-block-heading" id="h-ancient-roman-genomes-throughout-history">Ancient Roman Genomes Throughout History</h2>



In 2019, scientists sequenced the genomes of 127 individuals from 29 archaeological sites in and around the ancient city of Rome. To learn how the genetics of people living in the region changed over time, they sampled individuals who lived in the region over the past 12,000 years, from hunter-gatherers during the Mesolithic period (10,000–6,000 BCE) to the city’s inhabitants during the Medieval and Early Modern periods (700–1800 CE).&nbsp;



<figure class="wp-block-image size-large"><img loading="lazy" decoding="async" width="1024" height="667" src="http://35.88.189.111/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-1024x667.jpg" alt="A bronze statue of the Capitoline Wolf nursing Romulus and Remus. " class="wp-image-33447" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-1024x667.jpg 1024w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-300x195.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-768x500.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-880x573.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1-1180x768.jpg 1180w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Lupa_Capitolina_Rome-1.jpg 1600w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /><figcaption class="wp-element-caption">A bronze statue of the Capitoline Wolf nursing the mythical twin founders of Rome, Romulus, and Remus. </figcaption></figure>



The majority of the individuals that they studied lived in Rome during three key periods:&nbsp;



<ol class="wp-block-list">
<li>The Roman Republic (509–27 BCE): Following the overthrow of the last Roman king (Lucius Tarquinius Superbus) in 509 BCE, the ancient Romans established the first republic–a system of governance in which power was shared through a complex system of checks and balances, giving members of the public increasing rights over time. During this period, the ancestry of the ancient inhabitants of Rome started to appear similar to that of many present-day Mediterranean populations.&nbsp;</li>



<li>Imperial Rome (27 BCE–300 CE): This period spans the height of the Roman Empire, beginning when Augustus declared himself the first emperor of Rome and ending around the time when Emperor Diocletian established the Tetrarchy, dividing the rule of the Roman Empire among two emperors and their successors. This division paved the way for the eventual split of the empire into the Eastern and Western Roman Empires. During this period, ancient Rome’s inhabitants had highly variable ancestry, exhibiting strong connections to populations from the eastern Mediterranean and the Near East.</li>



<li>Late Antiquity (300–700 CE): During the Late Antique Period, Rome experienced a dramatic decline in its political influence and population size. The inhabitants of Rome continued to be highly diverse, but Central and Northern European-related ancestry started to become more common, possibly as a result of contact with invading populations, including the Visigoths, Vandals, and Lombards.</li>
</ol>



<h2 class="wp-block-heading" id="h-learn-more">Learn More</h2>



In honor of Italian-American Heritage Month, we have added 25 historical individuals from these three critical periods in Roman history to our Historical Matches feature. 



If you are a 23andMe+ Premium member, you can check it out to learn more about the ancient Romans and find out if you are distantly related to them or hundreds of other historical individuals.&nbsp;



Not yet a member? Learn more about <a href="https://www.23andme.com/compare-dna-tests/">all that 23andMe+ offers here</a>.

New Historical Matches Could Connect You to the Ancient Romans

With apologies to Walt Whitman, we all contain multitudes … of microbial cells, trillions of microorganisms that live in and on our bodies.



The<a href="https://www.genome.gov/genetics-glossary/Microbiome"> human microbiome</a> is vast and varied and accompanies us through our lives, changing as we age. As scientists continue to learn more about these microscopic ecosystems on our skin, mouths, and gut, we understand more and more about the sometimes surprising role they play in our health.



Researchers at 23andMe, in collaboration with the Michael J. Fox Foundation, recently published a study in <a href="https://www.nature.com/articles/s43856-024-00630-8">Communications Medicine</a> looking at the gut and oral microbiome of people with Parkinson’s disease. The study offers intriguing new insights that could help diagnose and monitor disease development and progression earlier.



“To our knowledge, this is the largest single study to test the relationships between both the oral and gut microbiomes and Parkinson’s disease, providing us with the statistical power to uncover potentially important associations,” said Keaton Stagaman, PhD, a postdoctoral research scientist at 23andMe and a co-author of the study.



<h2 class="wp-block-heading" id="h-gut-brain-axis">Gut-Brain Axis</h2>



Parkinson’s is a neurodegenerative disorder that affects movement and cognitive function. Research has found a strong ‘gut-brain axis’ that connects the central nervous system to the gastrointestinal tract, and studies have recently pointed to the potential link between Parkinson’s disease and the gut microbiome.



Along with Parkinson’s, changes in the gut microbiome have been linked to other conditions, including<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10012812/"> inflammatory bowel disease</a>, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9657115/">Clostridium difficile infections</a>,<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6300652/"> autoimmune disorders</a>,<a href="https://hms.harvard.edu/news/changes-gut-microbiome-may-increase-type-2-diabetes-risk"> diabetes</a>, and obesity. The links are intriguing but not yet fully understood. That said, a better understanding of the microbiome and its role could be essential for diagnosing and treating many conditions.



The new research by 23andMe offers more evidence of the connection between Parkinson’s and changes in the gut microbiome.



<h2 class="wp-block-heading" id="h-different-types-of-microorganisms">Different Types of Microorganisms</h2>



For this study, scientists used microbiome data from saliva and stool samples of people with and without Parkinson’s disease.



Scientists have identified about 1,000 microbial species in the human mouth, whereas the human gut has the densest collection of microorganisms in the body.<a href="https://www.ncbi.nlm.nih.gov/books/NBK562894/"> According to the National Institutes</a> of Health, the large intestine has as many as 100 billion to one trillion cells per milliliter and is among the densest microbial ecosystems ever observed.



<figure class="wp-block-image aligncenter size-large"><img loading="lazy" decoding="async" width="1024" height="896" src="http://35.88.189.111/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-1024x896.png" alt="" class="wp-image-33430" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-1024x896.png 1024w, https://blogcms.23andme.com/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-300x263.png 300w, https://blogcms.23andme.com/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-768x672.png 768w, https://blogcms.23andme.com/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-880x770.png 880w, https://blogcms.23andme.com/wp-content/uploads/2024/10/suppFig4_withinSources_functional_corr_network_KO_v1-1180x1033.png 1180w" sizes="auto, (max-width: 1024px) 100vw, 1024px" /><figcaption class="wp-element-caption">Images showing the clustering of different families of microorganisms from the gut and saliva of people with and without Parkinson&#8217;s disease. </figcaption></figure>



Because of the vast number of different microorganisms, 23andMe scientists in this research used sequence data to group those organisms into Operational Taxonomic Units or closely related types of bacteria. Using these groupings, the scientists were able to find significant differences in the type and abundance of microorganisms in the microbiome of people with Parkinson’s when compared to those without the disease.



This was the case in both stool and saliva samples. This is significant and suggests that using saliva samples, which are much simpler for patients and scientists to collect, is adequate for detecting differences in the microbiome for those with Parkinson’s.



<h2 class="wp-block-heading" id="h-the-findings">The Findings</h2>



In undertaking the study, the researchers thought there might be distinct microbial changes in people with Parkinson’s and that those changes could be seen in the early stages of the disease before many symptoms develop.



Among the signature differences researchers found was a higher diversity of microbes within the microbiome of those with Parkinson’s. This was the case even when considering other things that could affect the diversity of microbes, such as oral hygiene or constipation. In addition, the researchers said that the amount and diversity of microbes in samples was a good predictor of whether someone had Parkinson’s disease. Using a well-known machine learning algorithm called Random Forest, the team could predict whether a person had Parkinson’s or not 80 percent of the time.



The researchers also identified specific types of bacteria that differed between people with Parkinson’s and those who did not have the disease. The scientists believe that the findings might help find specific markers in the microbiome, specifically in saliva samples, that could be used to monitor for early signs of the disease.



Other studies have shown that changes in the gut microbiome may offer early indications of the onset of changes in a person’s motor functions.



<h2 class="wp-block-heading" id="h-learn-more">Learn More</h2>



Beyond the ability to use a person’s microbiome to evaluate the status of Parkinson&#8217;s, the paper also suggests that altering a person’s microbiome may offer another avenue for treating Parkinson’s symptoms. 



You can read the complete study in <a href="https://www.nature.com/articles/s43856-024-00630-8">Communications Medicine here.</a> 



Additionally, data from the Fox Insight PD Microbiome sub-study are available to qualified researchers <a href="https://foxden.michaeljfox.org/insight/explore/insight.jsp">here</a>.

Parkinson’s and the Microbiome

Recently, 23andMe significantly improved relationship estimates with two new updates: a new algorithm that improves predictions for distant relatives and HybridIBDSM, a new method to determine DNA Relatives.



These improvements are particularly beneficial for those who use 23andMe to find connections with their most distant DNA Relatives. Whether you&#8217;re a hobbyist dabbling in genealogy or a dedicated researcher tracing distant branches of your family tree, these changes will provide better insights to help you delve more into your genetic connections.



<h2 class="wp-block-heading" id="h-what-these-updates-mean-for-you">What These Updates Mean for You</h2>



With these updates, all customers will receive improved relationship predictions. These predictions will help you uncover older family connections that may date back much further than previously possible.



Existing 23andMe+ Premium and Total Health members will automatically be computed using the new HybridIBD algorithm. This will result in new and improved distant relatives. This update will provide more reliable insights for your genealogy research. 



All new 23andMe ancestry customers will be computed using the new HybridIBD algorithm.&nbsp;



Existing Ancestry and Health + Ancestry Service customers who want their results to be computed using the HybridIBD algorithm should upgrade to 23andMe+ Premium or Total Health.&nbsp;



<h2 class="wp-block-heading" id="h-ibd-the-science-behind-your-genetic-matches">IBD: The Science Behind Your Genetic Matches</h2>



Have you ever wondered what the signature of genetic relatedness is? The hallmark of genetic relatedness is long tracts of DNA shared between two people. Using shared DNA to estimate relatedness is called identity-by-descent (IBD). 



<figure class="wp-block-image alignright size-medium"><img loading="lazy" decoding="async" width="280" height="300" src="http://35.88.189.111/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-280x300.jpg" alt="" class="wp-image-33274" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-280x300.jpg 280w, https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-768x822.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-957x1024.jpg 957w, https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-822x880.jpg 822w, https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_-1102x1180.jpg 1102w, https://blogcms.23andme.com/wp-content/uploads/2024/08/61EhXFDmQL._AC_SL1500_.jpg 1121w" sizes="auto, (max-width: 280px) 100vw, 280px" /></figure>



We use IBD extensively within 23andMe, especially in our feature, DNA Relatives. DNA Relatives shows customers how close their relationships are.&nbsp; We are launching these two updates to improve the accuracy of our relationship predictions. The first update changes our method of making relationship estimates from IBD data. The second update improves the algorithm we use to detect IBD in the first place.



<h2 class="wp-block-heading" id="h-improved-relationship-predictions">Improved Relationship Predictions</h2>



You may have noticed that your predictions from 23andMe and other companies top out around the 5th or 6th cousins. This is regardless of how far down the list of relatives you scroll. For the better part of two decades, researchers have thought that the most distant relationship we could detect using IBD was around 15 degrees. This corresponds roughly to an 8th cousin who shares a common ancestor during the American Revolutionary War. It has long been possible to detect small shared segments that arose hundreds of generations in the past. However, it was thought that the long shared DNA segments detected among genotyped individuals in large databases like that of 23andMe represented relatively recent relationships.



Most relatives inferred by 23andMe are probably moderately distant, perhaps from 4th to 15th cousins. However, a new 23andMe paper released earlier this year demonstrated that the most distant relationship we can detect may be closer to a few hundred degrees. This corresponds to a common ancestor who lived thousands of years ago, perhaps before the rise of the Roman Empire.



There are two primary reasons existing relationship estimates do not go back that far. First, existing inference methods underestimate the probability that distant relatives share IBD. These estimators assume that each pair of distant relatives is connected through only one genealogical lineage. This can be a reasonable assumption when two relatives are closely related, but the assumption breaks down when we consider relationships whose common ancestors lived many generations in the past. In the distant past, each person shared many common ancestors with each of their relatives. Each person is connected to their ancestors by many different lineages, a phenomenon known as “pedigree collapse”.



<h2 class="wp-block-heading" id="h-published-research-on-relationship-inference">Published Research on Relationship Inference</h2>



<a href="https://www.biorxiv.org/content/10.1101/2024.05.13.594005v1.full.pdf">Our recent pape</a>r pointed out that the formulas underlying existing relationship inference methods don’t account for pedigree collapse. The fact that we are connected to each of our relatives many times over means that there are many paths for DNA transmission, not just one. This leads to a higher probability than we thought of sharing DNA with very distant relatives. As a result, there is a reasonable chance of sharing DNA with someone through an ancestor who lived many hundreds or even thousands of years in the past.



The second reason existing relationship estimators underestimate relationships is that they are applied almost exclusively to pairs of individuals known to share IBD in the first place. Genetic testing companies use a two-step procedure to identify your relatives. First, they find people with whom they share IBD. Next, they use this IBD to estimate relationships. However, the formulas that underlie existing relationship estimators aren’t designed for this approach. Instead, the formulas assume that two putative relatives were selected regardless of whether or not they shared IBD. Until our recent paper, it wasn’t well understood that this unintended application of estimators profoundly affected the inferences they made.&nbsp;



Below, Figure 1A shows the result of estimating a relationship using an existing relationship estimator, i.e., without accounting for two people sharing IBD.



In comparison, Figure 1B shows estimates made when accounting for the fact that IBD is shared. Figure 1 shows that existing relationship estimates all have a ceiling of around 10 degrees and are profoundly biased for more distant relationships. In comparison, a new estimator that accounts for observed IBD can generate very deep relationship estimates. Moreover, the higher uncertainty in the latest estimates captures the true range of likely relationships.



<figure class="wp-block-image alignright size-medium"><img loading="lazy" decoding="async" width="194" height="300" src="http://35.88.189.111/wp-content/uploads/2024/09/Estimated-Degree-v-True-Degree-194x300.jpg" alt="Two graphs showing degree of relatedness." class="wp-image-33299" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/09/Estimated-Degree-v-True-Degree-194x300.jpg 194w, https://blogcms.23andme.com/wp-content/uploads/2024/09/Estimated-Degree-v-True-Degree-661x1024.jpg 661w, https://blogcms.23andme.com/wp-content/uploads/2024/09/Estimated-Degree-v-True-Degree-568x880.jpg 568w, https://blogcms.23andme.com/wp-content/uploads/2024/09/Estimated-Degree-v-True-Degree.jpg 678w" sizes="auto, (max-width: 194px) 100vw, 194px" /></figure>



Figure 1: Existing and new relationship estimates. A) A relationship estimator that does not account for the fact that at least one segment of IBD is observed. B) An estimator that accounts for observing at least one segment of IBD.&nbsp;



<h2 class="wp-block-heading" id="h-introducing-hybridibd-exceptionally-accurate-dna-matching">Introducing HybridIBD: Exceptionally Accurate DNA Matching</h2>



The new DNA relationship estimates described above rely on accurate IBD detection. HybridIBD is a new IBD detection algorithm that combines strengths from two separate 23andMe IBD algorithms to dramatically improve IBD detection. Let&#8217;s take a look at these two algorithms.



<ul class="wp-block-list">
<li>phasedIBD compares matches between phased genomes, separated into distinct parental contributions. It excels at finding the short IBD segments that connect you to distant relatives. With phasedIBD, segments down to 5 cM or shorter can be identified reliably. This is important for accurately identifying distant relatives!</li>



<li>IBD64 works by comparing unphased genomes, which gives it an advantage for finding long IBD segments shared between close relatives since these are often considerably fragmented by phasing errors. For a more detailed assessment of phasedIBD and IBD64, see the <a href="https://doi.org/10.1093/molbev/msaa328">paper authored by 23andMe scientists in Molecular Biology and Evolution</a>.</li>
</ul>



With HybridIBD, every new genome is first analyzed by phasedIBD to find distant relatives. Then, any pair sharing a significant amount of IBD has refined their IBD using IBD64. This dual approach leverages the strengths of each algorithm, improving the overall accuracy of DNA Relatives.



We&#8217;ve developed a robust and scalable pipeline for HybridIBD that processes new customers against our database of over 15 million individuals, discovering approximately 300 million new relationships daily!



<h2 class="wp-block-heading" id="h-benefits-for-23andme-customers">Benefits for 23andMe Customers</h2>



When the new relationship estimators are implemented, all 23andMe customers can expect improved distant relative predictions for many relatives currently predicted as second cousins or higher. &nbsp;Customers will also see improvements in some close relationship predictions, especially first cousins, as the new estimator better accounts for age differences between you and your relatives.



Customers with Ashkenazi Jewish ancestry will see particularly large improvements in their distant relative predictions because our new relationship estimator better accounts for pedigree collapse, which was particularly strong in the historical Ashkenazi population. The new, wider confidence intervals also better capture the true range of likely relationships.



Customers’ results computed with HybridIBD can expect further changes. First, the accuracy of distant DNA Relatives will increase significantly. With phasedIBD now responsible for identifying distant relatives, many previous identifications made by IBD64 will be superseded by more accurate matches from phasedIBD. Two particular improvements to call out are that customers with South Asian, West Asian, or North African ancestries will find fewer DNA relationships with customers with only European ancestry, and customers with East Asian ancestries will see significantly more accurate second, third, and fourth-cousin relationships.



<h2 class="wp-block-heading" id="h-learn-more">Learn More</h2>



If you’re curious to learn more about the science behind these updates, we recommend checking out these papers:



<ul class="wp-block-list">
<li><a href="https://doi.org/10.1101/2024.05.13.594005.">Ethan M. Jewett and the 23andMe Research Team (2024). Correcting model misspecification in relationship estimates bioRxiv.</a> </li>



<li><a href="https://doi.org/10.1093/molbev/msaa328">&#8220;Fast and Robust Identity-by-Descent Inference with the Templated Positional Burrows-Wheeler Transform&#8221; by Freyman, W. A., et al., in Molecular Biology and Evolution (2021).</a></li>
</ul>



<h2 class="wp-block-heading" id="h-find-out-more">Find out more</h2>



23andMe customers can see their<a href="https://you.23andme.com/reports/ancestry_composition_hd/"> Ancestry Composition</a>.&nbsp;



Are you still waiting to be a customer? Find out more about 23andMe’s<a href="https://www.23andme.com/compare-dna-tests/">&nbsp; Ancestry Service and other services</a>.

Improvements to DNA Relatives: New HybridIBD Algorithm and Relationship Predictions

Common medications for conditions like anxiety, depression, or high cholesterol or even to limit the growth of some cancers, may not work as well for some of us because of our genetics.



Yet few of us know before we are prescribed an SSRI for depression, say, or a statin for high cholesterol, that we have a genetic variant that may impact how our bodies process those medications.



What if you and your doctor knew this beforehand?



<h2 class="wp-block-heading" id="h-open-your-genetic-medicine-cabinet">Open Your (Genetic) Medicine Cabinet</h2>



This week, we launched an upgrade to Medicine Cabinet, a feature for 23andMe+ Premium members that allows them to more simply check how their genetics may impact the medications they are currently taking.*



This version of the feature is also another way customers learn more about genetics&#8217; role in processing certain medications.* Most people have at least one genetic variant that may alter how their bodies process certain commonly prescribed drugs.



<figure class="wp-block-image size-full"><img loading="lazy" decoding="async" width="640" height="740" src="http://35.88.189.111/wp-content/uploads/2024/10/medCabinet-CommsBanner-640x740-1.jpg" alt="" class="wp-image-33443" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/medCabinet-CommsBanner-640x740-1.jpg 640w, https://blogcms.23andme.com/wp-content/uploads/2024/10/medCabinet-CommsBanner-640x740-1-259x300.jpg 259w" sizes="auto, (max-width: 640px) 100vw, 640px" /></figure>



<h2 class="wp-block-heading" id="h-what-is-pharmacogenetics">What is Pharmacogenetics?</h2>



The FDA lists<a href="https://www.fda.gov/medical-devices/precision-medicine/table-pharmacogenetic-associations"> dozens of medications with &#8220;pharmacogenetic associations&#8221;</a> and continues to add more.&nbsp;



<a href="https://www.cdc.gov/genomics-and-health/about/pharmacogenetics.html">Pharmacogenetics</a> is the study of how single DNA variants affect how you respond to medication. While many of these <a href="https://www.fda.gov/medical-devices/precision-medicine/table-pharmacogenetic-associations">pharmacogenetic associations</a> have been known for years, few people are tested before being prescribed many of these medications. 23andMe was the first direct-to-consumer genetics company to receive <a href="https://www.fda.gov/news-events/press-announcements/fda-authorizes-first-direct-consumer-test-detecting-genetic-variants-may-be-associated-medication">FDA authorization for its Pharmacogenetic Report</a>s*.&nbsp;



23andMe&#8217;s Medicine Cabinet feature puts more information directly in customers&#8217; hands. It allows 23andMe+ Premium members to easily input the medications they&#8217;re using into the feature manually or, for iOS users, through Apple&#8217;s HealthKit and save that information. Based on their Pharmacogenetic reports, they are then alerted of possible DNA-medication interactions.



That way, customers can more proactively monitor additional medication insights over time, as their medication may change or other pharmacogenetic associations become more known.&nbsp;&nbsp;



Of course, genetics is just one factor that influences how you process medications. Other factors, like age, weight, liver and kidney function, drug interactions, or even some foods, also play a role.



<h2 class="wp-block-heading" id="h-23andme-s-pharmacogenetic-reports-nbsp">23andMe’s Pharmacogenetic Reports&nbsp;</h2>



Currently,<a href="https://www.23andme.com/test-info/pharmacogenetics/"> 23andMe&#8217;s Pharmacogenetic Reports</a> examine variants in three genes affecting how individuals metabolize or transport about two dozen medications.



For example, 23andMe offers reports that look at variants in the genes CYP2C19, DPYD, and SLCO1B1, which are involved in processing specific medications. The CYP2C19 enzyme helps metabolize many commonly used drugs, such as proton pump inhibitors, the antiplatelet clopidogrel, and certain antidepressants. The DPYD gene encodes the DPD enzyme, which helps break down fluoropyrimidine chemotherapy medications, including fluorouracil (5-FU) and capecitabine. The SLCO1B1 gene encodes the SLCO1B1 protein, which helps transport cholesterol-lowering statins into the liver for removal from the body.



Knowing your underlying genetics could help you and your doctor ensure the effectiveness of some of your prescribed medications.&nbsp;



<h2 class="wp-block-heading" id="h-learn-more">Learn More</h2>



Medicine Cabinet will help 23andMe+ Premium members more easily monitor those medications and provide updates on newly identified pharmacogenetic associations or additional 23andMe reports.



This version of Medicine Cabinet is available to 23andMe+ Premium members in the United States. Learn more about <a href="https://www.23andme.com/membership/">joining 23andMe+ Premium here</a>.



<hr class="wp-block-separator has-alpha-channel-opacity"/>



*23andMe PGS Pharmacogenetics reports: The 23andMe test uses qualitative genotyping to detect 3 variants in the CYP2C19 gene, 2 variants in the DPYD gene, and 1 variant in the SLCO1B1 gene in the genomic DNA of adults from saliva to report and interpret information about the processing of certain therapeutics to inform discussions with a healthcare professional. It does not describe if a person will or will not respond to a particular therapeutic. Our CYP2C19 Pharmacogenetics report provides certain information about variants associated with the metabolism of some therapeutics and provides interpretive drug information regarding the potential effect of citalopram and clopidogrel therapy. Our SLCO1B1 Pharmacogenetics report provides certain information about variants associated with the processing of some therapeutics and provides interpretive drug information regarding the potential effect of simvastatin therapy. Our DPYD Pharmacogenetics report does not describe the association between detected variants and any specific therapeutic. Results for DPYD and certain CYP2C19 results should be confirmed by an independent genetic test prescribed by your own healthcare provider before taking any medical action. 



Warning: 



Test information should not be used to start, stop, or change any course of treatment and does not test for all possible variants that may affect metabolism or protein function. The PGS test is not a substitute for visits to a healthcare professional. Making changes to your current regimen can lead to harmful side effects or reduced intended benefits of your medication, therefore consult with your healthcare professional before taking any medical action. For important information and limitations regarding Pharmacogenetic reports, visit <a href="https://www.23andme.com/test-info/pharmacogenetics/">23andme.com/test-info/pharmacogenetics/</a>

Take a Peek Inside 23andMe’s Upgrade to the Medicine Cabinet Feature

23andMe&#8217;s new <a href="https://blog.23andme.com/articles/new-23andme-update-connects-many-african-american-customers-to-southern-roots">African American Genetic Groups feature</a> leans heavily on science, but it also relies on the well-crafted writing of Jalen Robinson, a third-year medical student at Morehouse School of Medicine who worked over the summer as an intern with the 23andMe Research Equity and Partnership team and helped build this feature. 



<figure class="wp-block-image aligncenter size-full"><img loading="lazy" decoding="async" width="536" height="695" src="http://35.88.189.111/wp-content/uploads/2024/10/Jalen-R-e1729182003758.png" alt="23andMe intern and Morehouse College of Medicine student Jalen Robinson." class="wp-image-33409" srcset="https://blogcms.23andme.com/wp-content/uploads/2024/10/Jalen-R-e1729182003758.png 536w, https://blogcms.23andme.com/wp-content/uploads/2024/10/Jalen-R-e1729182003758-231x300.png 231w" sizes="auto, (max-width: 536px) 100vw, 536px" /></figure>



Robinson, from Newton, Georgia, a rural community of 600, knows a lot about what places like his own hometown and others like it have to offer. Proud of where he comes from, he&#8217;s also motivated to give back and decided to go to medical school partly because he saw how the lack of access to healthcare in his community had affected the lives of friends and family members who died of preventable diseases. Becoming a doctor allows him to improve access to medical care in rural and underserved communities in the South.



His work on the African American Genetic Groups feature isn&#8217;t about healthcare but about recognizing these communities&#8217; cultural, political, and historical importance.



We sat down with Jalen to hear a little about what he learned during this project and what he hopes customers will use this feature.



<h2 class="wp-block-heading" id="h-why-medical-school">Why Medical School</h2>



<ol class="wp-block-list">
<li>You were motivated to attend medical school because you saw how a lack of access to healthcare in rural communities like yours costs lives. It&#8217;s not a parallel, but many small communities feel forgotten. Would helping people reconnect with their roots help people seeking to make these connections and communities?&nbsp;</li>
</ol>



Absolutely! I believe that helping people reconnect with their roots can be incredibly powerful for both individuals and communities. Growing up in a small town, I&#8217;ve experienced the deep pride and identity tied to shared history and values. Fostering these connections empowers residents to advocate for better healthcare and resources.



When people understand and feel more connected to their roots, they often become more engaged in their community&#8217;s well-being. This can lead to increased support for local healthcare initiatives, participation in outreach programs, or even a return home to contribute to the growth of their communities.



Ultimately, I hope this reconnection fosters a stronger sense of community ownership and collaboration. By working together, communities can identify their needs and develop solutions, ensuring everyone feels heard and has access to the care they deserve. Beyond improving health outcomes, this renewal can enhance the community spirit, creating a cycle of support and growth.



<h2 class="wp-block-heading" id="h-researching-african-american-genetic-groups">Researching African American Genetic Groups</h2>



<ol start="2" class="wp-block-list">
<li>You wrote up the descriptions of these broader African American Genetic Groups. Did you learn anything you didn&#8217;t already know or were surprised during your research?</li>
</ol>



Yes, I definitely learned a lot, which surprised me during my research. Growing up in southwest Georgia, I was unaware of the variety of genetic groups present in Georgia and throughout the southeastern United States. I didn’t realize how historical migration patterns have shaped genetic variations or how significant the influence of different regions and ancestral backgrounds has shaped the current genetic landscape.



During my research, I was particularly struck by the lasting impact that African Americans have had on culture, food, dance, music, language, and more. My purpose for this content section was to acknowledge the history of slavery and its role in the migration of African Americans to these areas while primarily highlighting the contributions and unique aspects of African Americans within these different groups. 



As I explored each genetic group, I was amazed by the rich histories associated with them. I discovered various languages, cuisines, and pastimes that reflect this heritage. Learning how African ancestry is celebrated through numerous parades, festivals, and events was inspiring. Additionally, I found that people can experience this history firsthand by visiting museums and historical societies dedicated to preserving and sharing these stories.



<h2 class="wp-block-heading" id="h-the-african-american-experience">The African American Experience</h2>



<ol start="3" class="wp-block-list">
<li>One of the fascinating aspects of DNA is that beyond just telling you about genetic predispositions or your ancestral background, it can reveal historical events, migration, and, as 23andMe&#8217;s Steven Micheletti has shown with his published work, the impact of the Transatlantic Slave Trade. What aspect of America&#8217;s history do you think this new feature reveals?</li>
</ol>



One of the most significant aspects this new feature reveals is the complex nature of the African American experience throughout history. By tracing genetic connections and migration patterns, we gain insight into the lasting impact of historical events like the Transatlantic Slave Trade and how they shaped family lineages and communities. 



This feature encourages uncomfortable conversations about events often overlooked in history. It allows us to confront the realities of slavery and understand how African Americans migrated to various regions within the U.S.



Moreover, it highlights the resilience of African Americans and their substantial contributions to communities. Their lasting impact is evident today in culture, language, food, music, and celebrations that honor African ancestry. Additionally, this feature gives individuals previously unaware of their ancestral lineage the chance to explore the genetic groups they are matched with, fostering a greater understanding and a deeper connection to their heritage. This newfound knowledge can empower people to celebrate their roots and fully engage with their cultural identity.



<h2 class="wp-block-heading" id="h-insights-from-23andme">Insights from 23andMe</h2>



<ol start="4" class="wp-block-list">
<li>You&#8217;ve used 23andMe, what did you learn most helpful for you?</li>
</ol>



Using 23andMe has been incredibly insightful for me. One of the most helpful aspects has been the ability to trace my ancestry and understand the diverse genetic backgrounds that contribute to my heritage. 



As an African American male, I knew my roots traced back to Africa, but it was exciting to pinpoint specific countries and see the percentage of my ancestry from each. I also found learning about my European, Indigenous American, and Caribbean ancestry composition fascinating. Discovering the specific genetic groups I’m connected to added even more depth to my understanding of my heritage.



I recently received my results, which showed a high probability of my ancestry being linked to African Americans from Mitchell and Baker Counties. This made sense, given my family&#8217;s long history in Baker County. 



However, I was surprised to find a 99 percent probability match to the Savannah River Basin African Americans genetic group, which includes Edgefield, Aiken, and Saluda counties in South Carolina, near the Savannah River that forms much of the South Carolina-Georgia border. I didn’t know of any ancestors from that area, so this discovery opened up new avenues for tracing my roots and exploring whether my ancestors might have migrated to Baker County.



<h2 class="wp-block-heading" id="h-some-surprises">Some Surprises</h2>



<ol start="5" class="wp-block-list">
<li>You also recently reviewed your ancestry results with Steven. What stood out as the most exciting thing for you and your family?</li>
</ol>



In addition to understanding my ancestry composition and specific genetic group connections, the health reports were the most exciting aspects for my family and me. My paternal family has a history of various cancers, while my maternal family has a history of diabetes and cataracts. I’ve always been curious about my risk for specific health issues.



The health report revealed that I had no variants detected for certain types of cancers 23andme tests for, which was reassuring. However, it noted that I am at elevated risk for Type 2 diabetes, something I was already aware of. Interestingly, I also had two variants detected for age-related macular degeneration, which indicates a slightly increased risk of developing that disorder. Additionally, I carry one of the two genetic variants tested for APOL1-related chronic kidney disease.



Before the health report, I was unaware of these findings and didn’t know I was at risk for these conditions. With this knowledge, I am empowered to take proactive steps and consult with my medical providers on ways to reduce the risk of developing them.



<h2 class="wp-block-heading" id="h-what-others-might-learn">What Others Might Learn</h2>



<ol start="6" class="wp-block-list">
<li>What do you hope customers take away from using this new feature?</li>
</ol>



I hope customers gain a greater sense of identity and belonging using this new feature. I want them to learn more about their ancestral composition, discover where their ancestors originated from, and understand any potential health risks they may face. 



This knowledge can empower them to connect more deeply with their heritage and make informed decisions about their health and well-being.

A map showing all the African American Genetic Groups

Working on 23andMe’s African American Genetic Groups Project

A group of people enslaved to the Confederate General Thomas Drayton, Hilton Head Island, South Carolina, in May 1862.

New 23andMe Update Connects Many African American Customers to Southern Roots

A new study by scientists in New Zealand determined that genetics has a much more significant impact on the risk of developing gout than previously thought.



Led by researchers at the University of Otago in New Zealand, the study published in the journal <a href="https://www.nature.com/articles/s41588-024-01921-5">Nature Genetics</a> used data from more than 2.6 million people with about 75 percent of that data from 23andMe customers who consented to participate in research.



<h2 class="wp-block-heading" id="h-ending-the-stigma">Ending the Stigma</h2>



While diet and lifestyle play a role, genetics have an outside influence on whether a person will develop <a href="https://www.23andme.com/topics/health-predispositions/gout/">gout</a>, this painful form of arthritis caused by the build-up of uric acid.



“Gout is a chronic disease with a genetic basis and is not the fault of the sufferer – the myth that gout is caused by lifestyle or diet needs to be busted,” said Professor Tony Merriman of Otago’s Department of Microbiology and Immunology, and the leading author of the paper.



Once associated with the gluttonous indulgence of someone like King Henry VIII, the researchers said they hoped that their study would illuminate the complicated biology of the disease and dispel some of the stigma around gout.



“This widespread myth causes shame in people with gout, making some people more likely to suffer in silence and not go and see the doctor to get a preventive drug that lowers urate in the blood and will prevent their pain,” Merriman said.&nbsp; 



<h2 class="wp-block-heading" id="h-genes-and-environment">Genes and Environment </h2>



As with many diseases, many factors influence the risk of developing gout. 



“People need to understand that while specific dietary factors — such as eating red meat — can trigger gout attacks, the fundamental&nbsp;cause&nbsp;is high urate levels, crystals in the joints, and an immune system primed to ‘attack’ the crystals – genetics plays an important role in all of these processes.”



The study identified 377 variants associated with gout, and 148 of those associations were identified for the first time. 



Many of these genetic variants are in or near gene regions involved in regulating urate levels and the mechanisms by which elevated uric acid in the blood, something called hyperuricemia, progresses to inflammation in the joints with gout. The study also identified several genes in the immune response associated with gout.



You can read the complete study in <a href="https://www.nature.com/articles/s41588-024-01921-5" target="_blank" rel="noreferrer noopener">Nature Genetics here</a>.

Latest Posts — Page 13