Earlier this month, we wrote about <a href="https://blog.23andme.com/23andme-customer-stories/jesss-story/">Jess</a>, who with the help of her 23andMe results discovered that 100 years ago her grandfather had been accidentally switched at birth with another baby boy and raised by<div id="attachment_22174" style="width: 236px" class="wp-caption alignright"><img loading="lazy" decoding="async" aria-describedby="caption-attachment-22174" src="https://blog-api.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-226x300.jpeg" alt="" class="wp-image-22174 size-medium" width="226" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-226x300.jpeg 226w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-662x880.jpeg 662w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam.jpeg 665w" sizes="auto, (max-width: 226px) 100vw, 226px" />Jess&#8217;s grandfather Phil and her great grandfather Sam.</div>Jewish immigrant parents while the baby he was switched with by an Irish Catholic family.

The reason Jess was able to figure this out is because for three years, another woman, Alice Plebuch, was working to unravel her own family mystery. It was Alice who ultimately reached out to Jess asking in an email if she’d learned something unexpected about her ancestry. 


Now we get to hear Alice’s side of this amazing story that has been posted on <a href="http://www.yourgeneticgenealogist.com/2015/02/switched-at-birth-unravelling-century_27.html">CeCe Moore’s blog</a>.
Alice was raised to believe that she was almost all Irish on both her mother and father’s side, but after testing with several different DNA testing services she learned that she was actually half Jewish. Her quest to figure out why took years of work, and required testing of several different family members as well as document searches and even creating a database to track all of her the relatives she discovered through testing. It’s instructive to see how careful Alice was with information, knowing that it could be difficult for some family members to digest and wanting to make sure she had all the facts first. Alice’s story
<div id="attachment_22272" style="width: 210px" class="wp-caption alignright"><img loading="lazy" decoding="async" aria-describedby="caption-attachment-22272" src="https://blog-api.23andme.com/wp-content/uploads/2015/03/Alices-father-200x300.jpg" alt="Alice's father, who turned out to be Sam's biological son." class="size-medium wp-image-22272" width="200" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father-200x300.jpg 200w, https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father-768x1152.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father-683x1024.jpg 683w, https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father-587x880.jpg 587w, https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father-787x1180.jpg 787w, https://blogcms.23andme.com/wp-content/uploads/2015/03/Alices-father.jpg 816w" sizes="auto, (max-width: 200px) 100vw, 200px" />Alice&#8217;s father, who turned out to be Sam&#8217;s biological son.</div>
is also informative about how a smart and resourceful person can use genetic testing and other records to uncover hidden family history.
What is also stunning, at least for us here at 23andMe, is that none of this would have – or even could have – come to light without genetic testing.


If Alice and Jess hadn’t tested there really wouldn’t have been any other way to uncover this hidden history. Even for CeCe – a genetic genealogists with <a href="http://www.yourgeneticgenealogist.com/p/about-me.html">years of experience</a> unraveling countless family stories – that Alice and Jess were able to figure this out was hard to believe.

23andMe Blog

23andMe Blog Team

The Other Side of the Story

Jessica has a black and white photo of her grandfather, Phil, standing next to her great grandfather, Sam.
In the photo, both father and son are staring into the camera and smiling. Now after uncovering something hidden about her ancestry, the photo takes on a new meaning.<img loading="lazy" decoding="async" class="alignright size-medium wp-image-22174" src="https://blog-api.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-226x300.jpeg" alt="Phil and Sam" width="226" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-226x300.jpeg 226w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam-662x880.jpeg 662w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Phil-and-Sam.jpeg 665w" sizes="auto, (max-width: 226px) 100vw, 226px" />
Phil, in a white t-shirt with his hair slicked back, towers over his dad and has a pretty distinctive chin dimple and big ears. His dad, Sam, with a gap-toothed grin and his sparse hair sticking up all over, has a very different set to his chin than his son.
The photo is an old one, something Jessica had looked at many times before. But after getting a message from another 23andMe user, Jessica realized something that was staring right at her. The two men – her grandfather and his father – couldn’t look more different.

<h6>Hidden Ancestry</h6>
Jessica’s fascinating post<a href="https://strangepilgrimage.wordpress.com/"> “And Who Would’ve Thought…,”</a> drew us in like few others. We won’t ruin the story for you. You need to read it yourself.
But in a brief exchange about her post, Jessica, who writes the<a href="https://strangepilgrimage.wordpress.com/"> “Strange Kind of Pilgrim”</a> blog, said she learned something that might have remained hidden if she hadn’t tested with 23andMe.
“I&#8217;m really thankful that this all came to light while there was still a chance of finding out what really happened,” she said. “I feel like, very slowly, I&#8217;m gaining some roots, and I&#8217;m grateful that I will have these stories and this information to pass down to my children so they can know where they came from.”
<h6>What Does it Mean?</h6>
Reading her story conjures up all sorts of questions about our upbringing, our ancestry and our identity. Your biology and your upbringing make up who you are, but which is more important? How much of what we are is dependent on our biology and how much on our ancestry?<img loading="lazy" decoding="async" class="alignright size-medium wp-image-22176" src="https://blog-api.23andme.com/wp-content/uploads/2015/02/Jess-photo-300x267.jpeg" alt="Jess photo" width="300" height="267" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo-300x267.jpeg 300w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo-768x683.jpeg 768w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo-1024x911.jpeg 1024w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo-880x783.jpeg 880w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo-1180x1050.jpeg 1180w, https://blogcms.23andme.com/wp-content/uploads/2015/02/Jess-photo.jpeg 1861w" sizes="auto, (max-width: 300px) 100vw, 300px" />
“The way you&#8217;re raised and the family who raises you can influence who you are in a big way, but I think the biology is always there,” said Jessica.
Jessica graciously let us post an excerpt of her story below, but you really should read the whole piece on<a href="https://strangepilgrimage.wordpress.com/"> her blog here</a>. Let us know what you think.
<h6>“And Who Would’ve Thought…It Figures”</h6>
 “In October I decided, rather on a whim, to order a genetics test from 23andMe.  It’s a company that compares your DNA to populations all over the world and lets you know where your ancestors likely hailed from.  I didn’t do this because I doubted my parentage at all (did you hear that, Mom?  I believe you.  Maybe other people who see us together assume I’m adopted, but I do not.  ), but I wanted to see my father’s side of the family tree more clearly.
“My dad passed away when I was very young.  His mother passed when he was very young, and his father died almost exactly two years after Dad did.  So while I had a vague idea of the Benson family heritage as communicated to me by my mother and aunt, I still felt a bit rootless.  I knew we were Russian and Polish Jews, but that’s it (and to be honest, I wasn’t even sure how Polish we were.  I came across a family tree partly filled out in my baby book, and it traces my paternal grandfather’s heritage to Russia and my paternal grandmother’s heritage to Turkey, but it went no farther back than that.)
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“Fast forward to December: The results came in, and they were…surprising.  I was on the phone with my mom at the time, and I think the first words out of my mouth were, “I’m Irish?!” … I wasn’t supposed to be Irish (or British).  Or Western European at all.  I was supposed to be a Russian, Polish Jew.  I was flummoxed.  My mom was flummoxed.  My aunt was flummoxed.  I really like the word “flummoxed.”  So descriptive.
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“Frustratingly, my search for answers had only turned up another mystery.  Even more infuriating, I couldn’t see a way of solving it.  The pertinent players were all long dead.  I could only figure that someone had fooled around on somebody in my family’s recent history and gotten away with a doozy of a lie.  
…
“One of the features of 23andMe is that they match you up with possible DNA relatives.  I have a whole list of 3rd to 4th and beyond possible cousins who share small segments of my DNA.  But my closest relative in the system was a predicted second cousin, who I only knew as P.  I didn’t contact P because I have nearly crippling social anxiety, and it’s a bit of an awkward conversation to initiate (Hi, I think we might be related.  Do you have any idea how?)  I hate awkward conversations like I hate the Patriots.  The antipathy runs true.
“This is all kind of important because a few days ago (has it really only been a few days?  What a short, strange trip it’s been) I received an email, not from P himself but from his cousin, A.  I’m so grateful that A was brave enough to ask those awkward first questions.  She asked if I had any known connections to the [Name removed]   family, and I answered that I didn’t.  I had never heard of the [family].  And then, interestingly, she asked me if I had expected my genetics results to report a sizable Ashkenazi component.  I had expected it, I told her, but it turns out, I’m not very much Ashkenazi.  Instead, I am unexpectedly Irish.  It’s all very mysterious, I confided.  And that’s when everything started to get a little weird.” 
 (READ THE REST OF THE STORY <a href="https://strangepilgrimage.wordpress.com/2015/01/22/and-who-wouldve-thought-it-figures/">HERE</a>)

Jess’s Story

So where did that red hair come from? 
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</code>by Kasia Bryc, 23andMe Population Geneticist 
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</code>Most people who see my unruly wild <img loading="lazy" decoding="async" class="alignright wp-image-21956 size-medium" src="http://35.88.189.111/wp-content/uploads/2014/11/Kasia1-197x300.jpg" alt="" width="197" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2014/11/Kasia1-197x300.jpg 197w, https://blogcms.23andme.com/wp-content/uploads/2014/11/Kasia1.jpg 369w" sizes="auto, (max-width: 197px) 100vw, 197px" /> 
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As a first generation immigrant from Poland, I don’t have any ancestors from Ireland.
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<h2>Recessive Trait</h2>
Yes, really, just take a look at my 23andMe Ancestry Composition results.
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Yet it is true that red hair is strongly tied to Ireland. Over 10 percent of 23andMe customers of Irish heritage, whose four grandparents were born in Ireland, have red hair. In most other parts of continental Europe, red hair is less common, and its frequency tends to hover between one and three percent. 
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</code>For me, my red hair holds special significance. Both my parents had brown hair, yet both my brother and I have red hair, thanks to the joys of recessive inheritance (No, we’re not adopted. And yes, our family relationships have been confirmed genetically through 23andMe). 
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</code>Red hair acts, for the most part, like a recessive trait, meaning that you need two copies of the red-hair genetic variant to see red hair. Which explains why my parents, each carrying one copy of the variant, didn’t have red hair, but could pass it on to their children by chance, which they did, twice. 
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As a child I puzzled over my hair color – it seemed rather poor camouflage, and surely ill-adapted – how could a trait as odd as red hair have come to be? 
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</code>That early fascination with human traits and evolution helped lead me to a career as a population geneticist. Nowadays I love wrangling with just such questions as I study the genetics of people across the globe. 
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</code>The red hair gene 
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</code>To dive into the genetics of red hair, we first have to understand the function of a gene called the Melanocortin 1 Receptor (MC1R). MC1R acts as a lever that toggles the cells to produce a brown or black pigment instead of producing a reddish yellow pigment. The color of the pigment, and how much is produced, leads to much of the diversity in appearance of humans around the world.
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Genetic mutations can change the normal function of MC1R, leading to a loss of function. That means that the protein the gene makes is changed so much that it doesn’t work as it should. So the pigment-producing cells don’t get their signal to make black-brown pigment that is so protective against the sun’s harmful UV rays,and instead produce more reddish yellow pigment, which, in your hair, gives it a red color.
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About 90 percent of 23andMe customers who report having red hair carry at least one of three of the most common genetic variants associated with red hair variants. Though there are other known and unknown variants involved in determining human pigmentation.
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<h2 class="tablepress-table-name tablepress-table-name-id-1">Do you carry one of these variants associated with red hair?</h2>
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<td class="column-1">R151C</td>
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<td class="column-1">R160W</td>
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Three variants highly associated with red hair among 23andMe customers. Not yet a customer? Visit our store!
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</code>The evolution of red hair 
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</code>For a long time, red hair was thought to be an adaptive trait. Not the hair color itself, but rather, red hair and lighter skin pigmentation are a bit of a package deal, and this lighter pigmentation was thought to be adaptive in northern Europe. Lighter skin color allows the skin to produce sufficient vitamin D when levels of light are low, when you don’t get sufficient levels of the vitamin through your food (such as from fish). So if you were a farmer in, say, Ireland, lighter skin would help you keep your vitamin D levels sufficiently high.
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However, there has been a surprising dearth of evidence for positive selection of red hair in Europeans, and there seems to be no association between red hair and the evolution of light skin in European populations. In contrast, the gene SLC24A5, which is involved with skin pigmentation, has a strong signal of selection. So it seems that for red hair, the vitamin D hypothesis isn’t really substantiated by science. 
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</code>Instead, the current theory most evolutionary scientists believe suggests that selective pressure to maintain proper protective black-brown pigmentation is highly constrained in regions closer to the equator that have strong sun exposure. The production of black-brown pigment, necessitating a functioning MC1R gene, helps shield cells from ultraviolet radiation that can increase the risk of skin cancer. 
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</code>In the far north, it seems, that selection may be relaxed. Comparing the human MC1R gene sequence to a chimpanzee’s genome suggests there was a lot of functional constraint on this gene&#8230; right up until humans migrated out of Africa. Mutations in MC1R that take away production of black-brown pigment may matter less where the sunlight isn’t as powerful. As a result, we observe these mutations, and the accompanying red hair. Sometimes, the mutations drift up in frequency by chance, and red hair becomes (more) common. 
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</code>For an even more nuanced contemplation of skin pigmentation and adaptation, and its possible relationship to the switch from hunter-gatherer lifestyles to farming, check out this read.
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<h2>Where are 23andMe customers with red hair from?</h2>
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</code>A closer look at the three most common red hair variants among 23andMe customers shows that red hair allele frequency in Europe does correlate with distance from the equator. The variant that is most common (and is involved in a third of red hair among 23andMe customers) is R151C. Unsurprisingly, this variant is most common in individuals whose grandparents were born in Ireland and in the UK.
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Over 50 percent of 23andMe redheads carry at least one copy of this variant. Are you one of them?
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The variant D294H is also most frequent in Ireland, but overall it is less prevalent, and found in a limited range: mostly Ireland, the UK, and France, Switzerland, and Belgium.
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Unlike the first two, the variant that I carry, R160W, isn’t most common in Ireland. Instead, it is found at its highest frequencies in Sweden and Lithuania, as well as other parts of Scandinavia, Central and Eastern Europe.
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So what do these maps of variants tell us about why red hair might have come to be?
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Well, there does seem to be a correlation between where the variants lie – each variant is most frequent above the 35th parallel, which suggests that there may really be a relaxed selective constraint on MC1R function this far north of the equator.
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<h2><img loading="lazy" decoding="async" class="alignright size-medium wp-image-22093" src="https://blog-api.23andme.com/wp-content/uploads/2015/01/redhair-world-300x300.jpg" alt="redhair world" width="300" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-300x300.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-150x150.jpg 150w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-768x768.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-880x880.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-271x271.jpg 271w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-372x372.jpg 372w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-574x574.jpg 574w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world-980x980.jpg 980w, https://blogcms.23andme.com/wp-content/uploads/2015/01/redhair-world.jpg 1000w" sizes="auto, (max-width: 300px) 100vw, 300px" />Research</h2>
In researching traits among 23andMe customers, I learned a lot about red hair. I was amazed at how the genetics of just one trait are so complex. For example, not everyone with two MC1R variants reports having red hair. Isn’t that how recessive traits should work?
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But instead, red hair variants aren’t completely penetrant, meaning they don’t always cause the trait. The variant that I carry, R160W, is especially illustrative: only 50 percent of individuals that carry two copies of this variant have red hair.
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On a personal level, I felt reassured that what I knew about my family’s history was consistent with what I found to be true about red hair. But even more, I realized just how widespread red hair variants are across Europe, especially its northern reaches.
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Kasia Bryc

No, I’m Not Irish

Thank your lucky clovers because almost everyone in the 23andMe database is connected to someone who is Irish, and plenty of others have at least a wee bit of Irish ancestry.<img loading="lazy" decoding="async" class="alignright wp-image-20593 size-medium" title="Irish Ancestry" src="https://blog-api.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-300x300.jpeg" alt="Kiss Me I'm Irish" width="300" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-300x300.jpeg 300w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-150x150.jpeg 150w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-768x768.jpeg 768w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-880x880.jpeg 880w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-271x271.jpeg 271w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-372x372.jpeg 372w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish-574x574.jpeg 574w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Kiss-Me-Im-Irish.jpeg 960w" sizes="auto, (max-width: 300px) 100vw, 300px" />
In honor of St. Patrick’s Day, 23andMe researchers looked at the aggregated and anonymous data of our customers to determine just how many had a connection, even if it was a small one, to the Emerald Isle.
What we found out was that about 87 percent of our more than 600,000 customers have at least a tiny amount of ancestry that is shared with someone of confirmed Irish descent. This doesn’t mean they have Irish ancestry, but that they share ancestry with someone who is Irish. We can do this by looking at DNA segments of a certain length that are shared with people of with confirmed Irish heritage.
For comparison’s sake in the US population about 11 percent of people report that they have Irish ancestry, according to the US Census. Boston has the highest concentration among U.S. cities with more than 20 percent listing themselves as Irish American. The total US population of more than 34 million people who report being Irish American dwarfs the 4.6 million people living in Ireland today. The total population of Ireland makes up only a very small fraction of all the people in the world today with Irish ancestry.
<img loading="lazy" decoding="async" class="alignright wp-image-20611 size-medium" src="http://35.88.189.111/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-300x203.jpg" alt="" width="300" height="203" srcset="https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-300x203.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-768x519.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-1024x692.jpg 1024w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-880x594.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy-1180x797.jpg 1180w, https://blogcms.23andme.com/wp-content/uploads/2014/03/Countries-of-Origin_Ireland-copy.jpg 1704w" sizes="auto, (max-width: 300px) 100vw, 300px" />Just in case you’re calling “blarney” on 23andMe’s estimates, it’s important to note a few things about how we derived our percentage. Because our researchers are looking at DNA segments that are very small – in this case about 7 centimorgans – that probably equates to a common ancestor with someone who is Irish within the last 10 to 12 generations. That’s way, way back.
Although our <a href="https://blog.23andme.com/articles/23andme-makes-more-improvements-to-ancestry-features" target="_blank" rel="noopener noreferrer">Ancestry Composition</a> tool can tell you what percentage of your DNA comes from populations around the world, breaking down the Asian, African or European ancestry. It also can give you finer detail, but the overlapping nature of DNA means that it groups Irish and British ancestry together. To get a better idea of Irish ancestry, customers can look at our Countries of Ancestry tool. This can show a customer DNA they have in common with other people who have confirmed ancestry from various countries, including Ireland. Our researchers used aggregated and anonymous data from all of our customers to determine what the percentage of customers who have shared segments of DNA with people who have confirmed Irish ancestry.
Ultimately we think the numbers mean you don&#8217;t need to to be Irish to be connected to someone who is.

Irish Ancestry — Page 2

The Other Side of the Story

Jess’s Story

No, I’m Not Irish

23andEire

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