The question: What does DNA look like?
While many of the 23andMe scientists have purified DNA more times than we’d like to remember, there are a fair number of people here (on the science team and on the engineering and business teams) who’ve never spent any time at the lab bench. We love all things DNA around here, so we recently set out to make sure everyone at 23andMe has gotten up close and personal with some Gs, Cs, Ts, and As.
We didn’t use human DNA — instead we isolated the genetic material of strawberries (click here for instructions). It’s pretty simple: smash up some strawberries with some soap and salt, add some rubbing alcohol, and voila! DNA!
As you can see in the pictures and video below, it’s an activity that is fun for all ages!
[minislides]
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23andMe Blog

23andMe Blog Team

The Answer: Snot

<img loading="lazy" decoding="async" class="alignright alignnone size-full wp-image-308" style="float: right;" title="omim1" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/omim1.jpg" alt="" width="347" height="254" srcset="https://blogcms.23andme.com/wp-content/uploads/2008/06/omim1.jpg 632w, https://blogcms.23andme.com/wp-content/uploads/2008/06/omim1-300x220.jpg 300w" sizes="auto, (max-width: 347px) 100vw, 347px" />
You may have already read about 23andWe and the ”<a href="https://blog.23andme.com/2008/01/21/the-power-of-we/" target="_blank" rel="noopener noreferrer">Power of We</a>” in earlier blog posts.
As the research arm of 23andMe, we&#8217;re hoping 23andWe can produce valuable discoveries about the genetic roots of diseases, conditions, and traits that are little-studied due to funding limitations, logistical obstacles or simple lack of interest among scientists. 23andMe&#8217;s payoff could prove enormous by offering insights that may eventually lead to risk predictions, diagnostics, treatments or even cures for diseases.
At 23andMe, we are all about grand ideas with big potential, and we are committed to realizing our vision, but how do you even start such a big project? You begin at the beginning, of course.
<h6>Where do you begin?</h6>
When we first started thinking about the traits we wanted to study in 23andWe, we faced a big problem. Out of all the possible traits out there, which ones should, we study first?
It’s both an overwhelming and wonderful problem to have, and one, I think, is pretty unique in the scientific community.
Most academic human genetics labs don’t have the luxury of splitting their research resources amongst many different problems. Subject recruitment, genotyping, and analysis are so difficult and expensive for even one trait that it’s usually feasible for only the largest and most well-funded centers to do this type of work. Limited funding usually also means that only the traits and diseases that are considered really serious get studied.
<h6>Unique Opportunity</h6>
In 23andWe, we saw a unique opportunity to tackle interesting and important questions about biology and disease that have so far been largely left unanswered.
Focusing on what has traditionally been understudied helped narrow down our field of research questions a little bit, but not that much. Frankly, not that many traits and diseases have been studied very well. So we had to apply a few more filters.
We wanted to pick topics that 
&#8211; Are relatively simple, because we have to walk before we can run. 
&#8211; Are easy to capture accurately over the Internet (which for now will involve online surveys). 
&#8211; Will apply to a wide swath of the population. 
&#8211; Already have some evidence in the literature for having a genetic basis
<h6>Tongue Curl</h6>
I can’t tell you how many <a href="https://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed" target="_blank" rel="noopener noreferrer">PubMed</a> (a biomedical literature search engine sponsored by the National Institutes of Health) searches we’ve done, nor how many 40-, 60-, and 80-year old papers we had to dig up to find some of the information we needed.
It’s been a fascinating project to work on. Did you know that people have been studying the inheritance of <a href="https://www.flickr.com/groups/97912899@N00/" target="_blank" rel="noopener noreferrer">tongue curling</a> for close to <a href="https://www.ncbi.nlm.nih.gov/pubmed/16588317?dopt=Abstract)" target="_blank" rel="noopener noreferrer">70 years</a> ? Turns out it’s not the simple <a href="https://en.wikipedia.org/wiki/Mendelian_inheritance" target="_blank" rel="noopener noreferrer">Mendelian</a> trait your high school biology <a href="http://udel.edu/~mcdonald/mythtongueroll.html" target="_blank" rel="noopener noreferrer">teacher told you</a> it was. Instead, tongue curling ability is probably determined by a mix of genetic and environmental factors.
<h6>Serious Conditions</h6>
It’s not all about tongue curling though. We’ve also been delving into the literature on many more serious health issues that affect large segments of the population but have not yet received as much attention as they deserve. These topics range from dyslexia to endometriosis, to migraine. We plan to collaborate with experts in the scientific and medical communities to push forward the limits of our knowledge on these important topics, with the long-term goal of helping to improve the quality of people’s lives.
In the coming months, you’ll start seeing the fruits of our labor as we roll out our first 23andWe projects. Of course, this is just the beginning. We’re going to spend countless more hours scanning our PubMed search results and fighting with the scientific journals’ user-unfriendly websites. And our thought processes, methods, and goals will continue to evolve as we gain experience and accumulate data. But it’s all worth it because the rewards are potentially great.
Stay posted…

Tackling Tongue-Curling: The Challenge of 23andWe

A large international collaboration of researchers has tripled the number of SNPs associated with Crohn’s disease, an inflammatory bowel disease that affects about 500,000 Americans. Their results were published online Sunday in <a href="https://dx.doi.org/10.1038/ng.175" target="_blank" rel="noopener noreferrer">Nature Genetics</a>.
<img loading="lazy" decoding="async" class="alignright alignnone size-full wp-image-311" style="float: right;" title="illu_small_intestine" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/illu_small_intestine.jpg" alt="" width="300" height="209" />
Data from more than 16,000 people with European ancestry — 8,059 from a combination of three previously published reports, a new set of 2,325 patients and 1,809 control subjects, and a group of 1,339 families — identified 21 new SNPs associated with Crohn’s disease and confirmed 11 previously implicated SNPs.

Although many of the SNPs described in the report only slightly impact the risk of developing Crohn’s, the findings could be important in helping researchers understand the basic biology of the disease.
“Studies such as this are not about developing diagnostic tests, but about identifying targets for new drug therapies. Crohn’s disease can be a very serious condition, often requiring surgery, and the sooner we can understand the underlying causes, the sooner we will be able to devise new treatments to help our patients,” said study author Dr. Miles Parkes.
Some of the newly identified SNPs are in (or near) genes linked to diseases other than Crohn’s, including type 1 diabetes, arthritis, psoriasis, and asthma. This highlights “the important relationships between different diseases and, as such, may offer valuable insights into the pathways that lead to common symptoms such as inflammation,” said Dr. Mark Walport, director of the <a href="http://www.wellcome.ac.uk/" target="_blank" rel="noopener noreferrer">Wellcome Trust</a>, one of the funding agencies that supported the study.
The researchers suspect there are many more genetic associations left to find for Crohn’s disease.
“These [SNPs] explain only about a fifth of the genetic risk, which implies that there may be hundreds of genes implicated in the disease, each increasing susceptibility by a small amount,” said the study’s lead author, Jeffrey Barrett.
Out of a possible total of 46, 80% of people will have between 17 and 25 copies of the riskier versions of these SNPs. Because there are so many of these SNPs — and because the riskier versions are often more common than their less risky counterparts — even people at the high end of the distribution are not much more likely than average to develop Crohn’s disease.

Number of SNPs Associated with Crohn’s Disease Triples

Many cancer patients who receive high doses of chemotherapy or radiation undergo a bone marrow transplant to replace blood cell-generating tissues that are killed as part of their treatment. But after a transplant these patients face a new challenge — opportunistic infections that take advantage of their weakened immune systems.
<img loading="lazy" decoding="async" class="right" title="aspergillus" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/aspergillus.gif" alt="Aspergillus" width="208" height="207" />Aspergillus fumigatus
One common and life-threatening infection among bone marrow transplant patients is invasive aspergillosis (IA), which is caused by the fungus Aspergillus fumigatus. About 10% of bone marrow transplant recipients are affected by invasive aspergillosis (IA). An estimated 30% of those affected will die within three months.
A study published in the June issue of <a href="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000101">PLoS Genetics</a> shows that a SNP in the gene encoding a protein called plasminogen significantly affects the risk of developing IA after a bone marrow transplant. Compared to transplant patients with the GG genotype at rs4252125, the risk of developing IA was increased 3.0 fold in people with the AG genotype, and 5.6 fold for people with the AA genotype.

Zaas et al began their study of IA in bone marrow transplant patients by looking for clues in several genetically distinct strains of mice. The researchers mimicked a bone marrow transplant in the mice by giving them drugs that suppressed their immune systems. They then exposed the animals to the Aspergillus fungus.
The researchers found that some mouse strains survived Aspergillus infection, while others did not. A SNP in the plasminogen gene correlated with Aspergillus susceptibility, and the researchers considered it a likely candidate because other scientists had recently indicated that proteins in the same biological pathway as plasminogen are important for fighting off infectious pathogens.
Armed with this clue from mice, Zaas et al turned their attention to humans. They followed a group of 230 immunosuppressed bone marrow transplant recipients for one year. Just as they had seen in the mice, the researchers found that IA was associated with a SNP (rs4252125) in the plasminogen gene.
Oddly, the association between rs4252125 and IA applies only 40 days or more post-transplant. The authors aren’t exactly sure why this is the case. It could be due to the low proportion of patients who are infected with Aspergillus in the first 40 days after their transplants. It could also be that until 40 days, when the transplanted bone marrow really starts to take hold, other risk factors swamp out the effect of rs4252125.
Laboratory tests showed that the plasminogen protein encoded by rs4252125, which is made in the liver, binds to Aspergillus fungus. And computer models indicate that the SNPs found in both mice and humans change the protein in a way that alters binding to the fungus, giving a possible explanation for why the SNP affects susceptibility to IA.
Though more research and evaluation is required before clinical applications can be developed based on this research, the authors write in the conclusion of their report that their results have “important implications for pre and post transplant care, and may also have implications for the management of other immune-compromised patients. For example, genetic testing could identify high risk individuals who may benefit from use of broad-spectrum antifungal agents or enhanced monitoring for infection.”

Genetics and Risk for Infection After Bone Marrow Transplant

<img loading="lazy" decoding="async" class="alignright size-full wp-image-288" style="float: right;" title="ruraliceland" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/ruraliceland.jpg" alt="" width="350" height="231" srcset="https://blogcms.23andme.com/wp-content/uploads/2008/06/ruraliceland.jpg 350w, https://blogcms.23andme.com/wp-content/uploads/2008/06/ruraliceland-300x198.jpg 300w" sizes="auto, (max-width: 350px) 100vw, 350px" />For the past 100 years, there has been a mysterious disease afflicting Icelanders. Called Hereditary Cystatin C Amyloid Angiopathy (or HCCAA), it causes severe brain hemorrhages and dementia in young adults. For those individuals who have the disease, life expectancy is usually no higher than 30 years. Scientists have determined that this disease is caused by a single mutation in the cystatin C gene. But until now, they had not yet discovered how this mutation arose, why it afflicts only Icelanders, and why it suddenly appeared within the last 150 years. A new collaboration between American and Icelandic scientists has helped to answer these puzzling questions about the origins of HCCAA by using Iceland’s Genealogical Database, which includes more than 80% of all Icelandic people who have ever lived. It also sheds light on the last 200 years of Iceland’s population history, and offers clues to understanding the interplay between genes and environment.  The researchers’ original goal — to use genetic and genealogical information to trace the common ancestor of every Icelander with HCCAA — proved unfeasible due to lack of data. But researchers did find a man born in 1684 north of Iceland’s capital, Reykjavik, who was an ancestor to most carriers of the disease. Because the lineages of so many people with HCCAA converged on that person, it can be inferred that he also carried the deadly mutation in the cystatin C gene. Yet census records show he did not have a shortened life span. In fact, through the 18th century the average life span for a person with the HCCAA mutation was in the neighborhood of 65 years, about average for the period. In addition, there are no historical records of Icelanders suffering from this disease throughout the 17th and 18th centuries. So if the mutation existed in 1684, why did no one show any symptoms until the mid-19th century? The researchers&#8217; next task was to find out when in Iceland’s history people did start showing symptoms of HCCAA. By again using Iceland’s extensive genealogical database, researchers found a significant change in life expectancy for those carrying the mutation, starting in the 19th century. It appears that individuals with the disease who were born after 1825 began to have significantly shorter life spans. By the year 1900, the average life span for HCCAA carriers had dropped to 30 years, where it remains today. But why did life spans not start decreasing until the early to mid-19th century, when records show that this mutation had been present among Icelanders since the 17th century? What changed for the people of Iceland? The answer may lie in their diet. The researchers noticed that, prior to the 19th century, the diet of Icelanders consisted mostly of whey-preserved offal (animal entrails and organs) as well as meat, dried fish, and butter. In other words, a diet low in carbohydrates and salt. However, post-19th century, imports from mainland Europe increased dramatically, and a typical Icelandic diet began incorporating processed carbohydrates and salt (to preserve food). The researchers argue that the movement of imports from Reykjavik to more isolated regions in Iceland throughout the 19th century mirrors the appearance and spread of HCCAA symptoms. As these new kinds of foods spread from the capital to smaller towns and villages, the deadly symptoms of HCCAA did as well. Therefore, it appears that the traditional Icelandic diet ‘masked’ the deadly symptoms of HCCAA, and it wasn’t until they began to eat more processed foods, higher in carbohydrates and salt, that these ‘masking’ effects diminished. The researchers did not speculate on the mechanism by which diet may be triggering the symptoms of HCCAA; but his study is significant for a variety of reasons. First, it is a fascinating example of how environment — in this case, diet — can affect a genetic mutation. In addition, this study is important due to a possible connection between the cystatin C gene and Alzheimer’s disease. Knowing more about the effects of a single mutation in this gene brings us another step toward understanding the complex genetics of Alzheimer’s. The mystery of HCCAA&#8217;s origins was tackled jointly by scientists in Iceland and at Johns Hopkins in the United States. It is reported in June 26 issue of <a href="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000099" target="_blank" rel="noopener noreferrer">PLOS Genetics</a>

Iceland’s Deadly Disease Mystery

What can we learn from studying how variations of human genes are spread out around the world?
A lot, said population geneticist and Harvard junior fellow Sohini Ramachandran, who spoke at 23andMe this week.
Ramachandran focused on how genes spread from one continent to another, and how they vary within each region as well.
As an example, she referenced some of the research she did as a graduate student at Stanford, tracing how genetic diversity decreases as the populations sampled get geographically farther away from Africa, long considered the cradle of humanity. For the purposes of measuring genetic diversity, distance from Africa is measured along the same paths that people presumably took at they migrated around the world — over land, without crossing major oceans.
<img decoding="async" class="alignright size-full wp-image-283" style="float: right;" title="rsplosg07fig3b" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/rsplosg07fig3b.jpg" alt="" width="401" srcset="https://blogcms.23andme.com/wp-content/uploads/2008/06/rsplosg07fig3b.jpg 866w, https://blogcms.23andme.com/wp-content/uploads/2008/06/rsplosg07fig3b-300x279.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2008/06/rsplosg07fig3b-768x713.jpg 768w" sizes="(max-width: 866px) 100vw, 866px" />Genetic diversity in the Americas (the darker the color, the more diverse the populations).
<h6>Genetic Diversity</h6>
As people migrated, Ramachandran said, genetic diversity decreased due to what she called “serial bottlenecks.” In these cases, though a fairly large number of people might reach one spot, only part of that group would move farther on. By chance, some of the genes in the population would not make it into the new territory.



For this reason, Ramachandran said, the researchers find more diversity in DNA samples from African populations than they do in samples from American populations.

Because genetic diversity varies based on who got how far, Ramachandran doesn’t just study the genetic variations across continents but between continents as well.
<h6 class="MsoNormal">Guns, Germs Steel</h6>
One of the topics she looks at is how genetics could support the theories outlined by evolutionary biologist Jared Diamond in his 1998 book, <a href="https://www.pbs.org/gunsgermssteel/" target="_blank" rel="noopener noreferrer">Guns, Germs and Steel</a>. One section of the book she focused on — and which she called her favorite part — was Chapter 10, &#8220;Spacious Skies and Tilted Axes.&#8221;

Diamond proposed that continental expansion was partly dependent on how the landmasses are oriented, and that humans brought crops and technology with them as they did so. For example, because Eurasia is on an east-west axis, it was easier for humans to move plants and animals along that axis because the climate was similar. Ramachandran noted that a 2005 study found that humans and domesticated crops for farming spread from east to west about 3,000-5,000 years ago in Europe.


On the other hand, Diamond said, the Americas and Africa are oriented on a north-south axis and as people traveled north and south, they would have found that plants and animals they brought along couldn’t always adapt to the seasonal changes. For example, Diamond noted, the Indians in North and Central America had no pack animals because the llamas and alpacas never moved out of the Andes. And the corn grown in Mexico needed thousands of years to adapt to the changes in growing season and day-length to make its way up north.

<h6 class="MsoNormal">Genetic Differences in the Americas</h6>
If this holds true on a larger scale as Diamond suggested, then there should be population bottlenecks and more distinct genetic differences between populations across the Americas latitudinally (north-south) than there are longitudinally (east-west). Ramachandran also said that the distinct genetic differences between populations across the Americas latitudinally should be greater than the distinct genetic diversity seen longitudinally (east-west) across Eurasia.

Ramachandran and her colleagues <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.0030185" target="_blank" rel="noopener noreferrer">reported</a> on the genetic diversity of the Americas last year, but she says more data is needed for this region. She also thinks that Diamond’s proposed north-south axis of orientation isn’t quite right, arguing that it should run northwest-southeast. To better study the genetic diversities of the populations across this tilted axis, she and her colleagues change the way they view the map of the world.

If the planet were a ball, the point at which it would be spinning on someone’s finger might be the South Pole. Using points such as the southernmost area of South America, South Korea or Sri Lanka as the axis of rotation on which to turn the map, Ramachandran demonstrated how she and her colleagues can look at the genetic diversities of populations in the Americas and Asia and find patterns in the genetic variations that might not be so easily seen from other perspectives.

Ramachandran said she hopes to publish her research on the populations in the Americas soon. In the meantime, her talk illustrated how studying genetics can support theories raised about human origins in other areas of study such as archeology, anthropology and history.

Image from <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.0030185">PLoS Genetics: Wang et al, 2007</a>

A Genetic Look at “Guns, Germs and Steel”

<img loading="lazy" decoding="async" width="290" height="400" class="right size-full wp-image-281" style="float: right;" title="jessejamessmall" src="https://blog-api.23andme.com/wp-content/uploads/2008/06/jessejamessmall.jpg" alt="" srcset="https://blogcms.23andme.com/wp-content/uploads/2008/06/jessejamessmall.jpg 290w, https://blogcms.23andme.com/wp-content/uploads/2008/06/jessejamessmall-218x300.jpg 218w" sizes="auto, (max-width: 290px) 100vw, 290px" />Jesse James

Editor&#8217;s note: This post has been corrected from the original, which gave the incorrect location of Jesse James&#8217; grave. 


One of the most engaging features of 23andMe’s Personal Genome Service is a customer’s ability to trace his or her genetic ancestry using the mitochondrial DNA and the Y-chromosome.
Once customers learn their own ancestry, the Genome Sharing feature allows them to see how they compare with friends and family.
However, the ancestry section of 23andMe also allows customers to see how they compare to well-known individuals. In the maternal and paternal ancestry features, customers can view the haplogroup assignments of such figures as Thomas Jefferson, Genghis Khan and Bono.
<h6>Am I Related to Someone Famous? Sort of.</h6>
But how can anyone know the ancestry of someone like Thomas Jefferson, who has been dead for a few hundred years, or Genghis Khan, who has been dead for close to a thousand?
It turns out there are several ways to find out these well-known figures’ ancestry. The most obvious: Celebrities can sign up for 23andMe’s Personal Genome Service, just like the rest of us! For example, Jimmy Buffett and Warren Buffett have been interested for years in finding out whether their shared surname was an indication of common genetic ancestry. Unfortunately, their genetic profiles show the two are not closely related.
<h6>
 Founding Fathers&#8217; Haplogroups</h6>

But what about people like Thomas Jefferson?
He is no 23andMe customer, but this does not mean that scientists cannot trace his ancestry by other means. Tracing the maternal or paternal ancestry of any deceased individual is usually done by one of two ways: either getting DNA from the physical remains of the individual, or getting DNA from direct descendants of a relevant lineage.
He is no 23andMe customer, but this does not mean that scientists cannot trace his ancestry by other means. Tracing the maternal or paternal ancestry of any deceased individual is usually done by one of two ways: either getting DNA from the physical remains of the individual, or getting DNA from direct descendants of a relevant lineage.
In the cases of Thomas Jefferson and Benjamin Franklin, scientists used DNA from direct descendants of their ancestors. For example, in 1998 scientists inferred Jefferson’s paternal ancestry by analyzing the Y-chromosome of direct descendants of Jefferson’s paternal uncle (Jefferson had no confirmed sons).
<h6>Marie Antoinette and other Royal Haplogroups</h6>
Likewise, in the case of historical royalty such as Tsar Nicholas II of Russia or Marie Antoinette of France, extensive and detailed royal pedigrees make finding direct descendants a breeze.
Likewise, in the case of historical royalty such as Tsar Nicholas II of Russia or Marie Antoinette of France, extensive and detailed royal pedigrees make finding direct descendants a breeze.
In the case of the infamous outlaw Jesse James, a more direct approach was used. It had been widely believed that after James died in 1882, his body was buried at Mt. Olivet Cemetery in Kearney, Missouri. In order to test this hypothesis, scientists exhumed the body, extracting a few teeth. They compared DNA from the teeth to that of the great-grandson and great great-grandson of James’ sister. Scientists found an exact match between the extracted teeth and James’ sister&#8217;s descendants, thus confirming that the body in Mt. Olivet Cemetery was most likely that of Jesse James and establishing his ancestry to boot.

<h6>
How about Genghis Khan?</h6>
He is listed in our famous people sidebar as being a member of Y-chromosome Haplogroup C. But we do not have any information on his direct descendants alive today, nor do we have any preserved remains of his body. However, scientists have examined the Y-chromosomes of many present-day inhabitants of Mongolia (the ancestral home of Genghis Khan).
In doing so, they have found that about 8% of Mongolian males share the exact same DNA pattern in a highly variable part of their Y-chromosomes. Further analysis has revealed that this particular Y-chromosome type, which falls into haplogroup C, originated about 1,000 years ago and that its dispersal across Central Asia corresponds to the boundaries of the Mongol Empire. Historians have long noted Khan’s prolific nature; he is rumored to have fathered more than 40 sons, with some of his descendants also fathering many sons of their own. So it&#8217;s a good bet that we&#8217;re seeing Genghis Khan&#8217;s legacy in the 8% of Mongolian males alive today who have identical Y-chromosome signatures.
There are a number of ways we can determine the haplogroups of well-known figures — both past and present — and displaying information about these individuals adds to the fun of understanding and comparing the genetic ancestry of ourselves, our friends and family, and the rich and famous (or infamous).
Explore the origins of your ancestry at <a href="https://www.23andme.com/dna-ancestry/">23andMe.com</a>.

Haplogroups of the Rich and Famous

Roy King is a clinical psychiatrist at Stanford University. He’s also a scholar who uses genetics and archaeology to figure out how agriculture spread through Anatolia and the Mediterranean region of Europe more than 10,000 years ago.
Now Roy has another genetic puzzle to consider — himself.
With the help of 23andMe, he can now see how his own family tree — which has African American, Native American and Ashkenazi Jewish branches — is reflected in his genome.
Roy recently sat down with some of 23andMe’s scientists to look at his Ancestry Painting. (You can watch video of his conversation with 23andMe’s Matt Crenson below.)


An element of our Personal Genome Service, Ancestry Painting examines the 22 bi-parentally inherited chromosomes one segment at a time and determines for each stretch whether it was most likely inherited from ancestors in Africa, Europe or Asia. Roy’s painting is one of the most colorful our scientists have ever seen — an intricate patchwork of blue, orange and green. The colors indicate which segments of Roy’s DNA he inherited from ancestors in Europe, Asia and Africa respectively.
Though the pattern may look random to the untrained eye, it actually reveals a wealth of information about Roy’s ancestry. It also confirms a lot of what he has discovered in researching his genealogy.

For example, Roy has found records indicating that two 19th-century ancestors on his mother’s side were Native American. The orange stretches in his Ancestry Painting support that account. Native Americans tend to have predominantly orange paintings, with a smattering of blue indicating their descent from Ice Age hunters who lived in Siberia, a part of Asia with some European genetic influence.
According to Roy’s family tree about one-quarter of his ancestry should trace to Europe, because his paternal grandfather was an Ashkenazi Jewish man from New York City.
His other three grandparents were African American.
So why does his Ancestry Painting indicate 51% European ancestry, rather than something closer to 25%?
The reason is that like most African Americans, Roy has some European ancestry from the pre-Civil War era. Roy’s genealogical research suggests, for example, that his great-grandmother may have been the daughter of a white man who raped his great-great-grandmother. Another of Roy’s great-great grandmothers came from New Orleans, where research has shown that the African Americans average about 20% European ancestry.
For an illustration of how a person’s Ancestry Painting and family tree match up, take a look at this illustration of Roy’s pedigree.
Instead of labeling each oval (indicating a female) or square (male) with names and birthdates, we’ve given them colors. Green indicates a person who would typically be considered African American, blue a person of European descent and orange a Native American.
There appears to be more green in Roy’s family tree compared to his Ancestry Painting, due to the presumed presence of European ancestry among some of Roy’s African American ancestors. But other than that, the two illustrations of his ancestry look remarkably similar.

A Beautiful Ancestry Painting

<img decoding="async" src="https://blog-api.23andme.com/wp-content/uploads/2008/05/cocktail.jpg" alt="cocktail.jpg" class="right alignright">A new study in <a href="https://dx.doi.org/10.1038/ng.151" target="_blank" rel="noopener noreferrer">Nature Genetics</a> shows that the increased risk of developing cancer in the mouth, throat, voice box and esophagus due to drinking is partially offset by the rarer versions of two SNPs associated with alcohol metabolism.
Cancers of the oral cavity, throat (also called the pharynx), voice box (or larynx) and esophagus are collectively known as upper aerodigestive (UAD) cancers. <a href="http://findarticles.com/p/articles/mi_m0CXH/is_3_29/ai_n21041723/pg_1" target="_blank" rel="noopener noreferrer">Alcohol consumption</a> is known to be a significant risk factor for these cancers. Studies have shown that the areas of the body that come into closest contact with ingested alcohol are at highest risk of being affected by cancer.

The two SNPs associated with UAD cancers are both located in genes that are part of the alcohol dehydrogenase (ADH) enzyme pathway, a group of proteins that aids the body in metabolizing alcohol. The authors of the study hypothesize that the protective versions of the SNPs they found exert their effect on UAD cancers by changing the carcinogenic effects of alcoholic beverages. These SNPs had no effect among non-drinkers.
Hasibe et al studied six SNPs in ADH pathway genes in a total of 3,876 people with UAD cancers and 5,278 healthy controls, in hopes of finding DNA variants associated with these diseases. This large study group was comprised of three smaller study groups: one group from eastern Europe with 809 patients and 2,586 controls; one group from western Europe with 1,356 patients and 1,407 controls; and a final group from Latin America with 1,711 patients and 1,285 controls.
Both rs1229984 and rs1573496 were significantly associated with UAD cancers in the large study group and each of the smaller study groups individually.
When the researchers broke the patients into groups based on specific cancer type — oral/throat, voice box, and esophagus — they found that both SNPs impacted the risk of developing the subtypes of cancer to different extents (see the chart at the end of this post for details).
About 19 out of every 100,000 people is diagnosed with UAD cancer per year in the United States. Individually, the lifetime risks of developing these cancers are: oral/throat, 1 in 99; voice box, 1 in 274; and esophagus, 1 in 198.
Those who have one or two copies of the T version of rs1229984 were found to have 0.56 times the odds of developing UAD cancer compared to those with two C versions. For those who carry one or two copies of the G version of rs1573496, their odds of developing UAD cancer were 0.68 times those with two C versions. People who carry at least one T at rs1229984 and one G at rs1573496 were found to have 0.45 times the odds of developing UAD cancer compared to people who had no protective versions of either SNP.
The authors say that the exact mechanism by which the protective versions of these two SNPs are working is not clear. It is known that people with one or two copies of the T version of rs1229984 metabolize ethanol up to 100 times faster than people with two copies of the C version. The authors of this study speculate that this faster metabolism may protect tissues by reducing their exposure to the effects of alcohol.
The tables below sum up the results of this study. The “effect” of each SNP is the change in odds for carrying either one or two copies of the protective version.
<img decoding="async" src="https://blog-api.23andme.com/wp-content/uploads/2008/05/booze2.jpg" alt="booze2.jpg">

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