Editor&#8217;s note: This post has been changed to reflect 23andMe&#8217;s newly regulated product offering. 
Caitlin, a blogger and self-described nerd, titled her ode to 23andMe “<a href="http://desertdandelion.blogspot.com/2012/12/do-these-genes-make-my-butt-look-big.html">Do These Genes Make My Butt Look Big?</a>” 
<img loading="lazy" decoding="async" class="alignright size-medium wp-image-19480" src="https://blog-api.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-300x225.jpg" alt="Rob and Caitlin" width="300" height="225" srcset="https://blogcms.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-300x225.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-768x576.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-1024x768.jpg 1024w, https://blogcms.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-880x660.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2013/10/Rob-and-Caitlin-1180x885.jpg 1180w" sizes="auto, (max-width: 300px) 100vw, 300px" /> 
When she and her husband Rob gave each other the test kits as a gift, the two were captivated by the results, and like many things in her life, she went online to share.
The first thing Caitlin wanted to address was her relationship with Rob. The two had been together since high school, so long in fact that they began to look like each other she said. So some folks started asking, “Are you related?”
“Not so.” And 23andMe gave them the proof!
At first blush one might look at this young couple and see two fun loving, adventurous 28 year-olds. But Caitlin is a survivor of childhood cancer and Rob a combat veteran from the Iraq war. They have known their share of hardship, and yet, as a couple, life is about what’s new, what’s next and what they can learn. Testing with 23andMe was part of that exploration.
“(I)t can also show &#8230; where your family most likely came from, how much <a href="https://www.23andme.com/ancestry/deep/">Neanderthal DNA</a> you have, and what physical traits you&#8217;re most likely to have, given your genes,” said Caitlin.
When she first looked at her results, Caitlin started with the easy stuff, her predicted traits. Her genetics indicate that she’s likely to have Curly hair (check); that she would likely be near sighted (check), have green or brown eyes (check), and most likely have a big head – as Caitlin commented: “Yep, it&#8217;s huge”.
Then Caitlin moved to the health results. It did make her feel more assured about the veracity of the rest of the results and she became more proactive.
Caitlin took her report to her doctor to review.   Again, Caitlin felt empowered with the knowledge the results provided so she could have an educated discussion with her doctor.
Comparing their results, she and Rob discovered that, as prospective parents, their genes are a good fit.<img loading="lazy" decoding="async" class="aligncenter wp-image-19481 size-full" src="http://35.88.189.111/wp-content/uploads/2013/10/DSC_0496-1-scaled.jpg" alt="" width="2560" height="1714" srcset="https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-scaled.jpg 2560w, https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-1024x685.jpg 1024w, https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-300x201.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-768x514.jpg 768w, https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-880x589.jpg 880w, https://blogcms.23andme.com/wp-content/uploads/2013/10/DSC_0496-1-1180x790.jpg 1180w" sizes="auto, (max-width: 2560px) 100vw, 2560px" />
“We also found out that our child has only a 22 percent chance of being blue-eyed, that we are not related (even though many people have suggested the possibility given the resemblance between us), and that neither of us appear to carry any of the diseases they keep track of,” She said.
But for Rob the golden nugget was this, Caitlin has 2.9 percent Neanderthal DNA which puts her in the 89 percentile.
“Rob is slightly less Neanderthal than I am, which he&#8217;s pretty proud of. So there you have it, quite possibly the most nerdy gift I have ever given and received.”
Results not typical. Results vary due to unique differences in each individual’s DNA. On average, users receive at least one or two results that may help with proactively managing health.  23andMe’s services are not a substitute for professional medical or diagnostic advice.

23andMe Blog

23andMe Blog Team

Spit And Tell

<img loading="lazy" decoding="async" class="aligncenter wp-image-17185 size-full" title="underarm odor" src="http://35.88.189.111/wp-content/uploads/2013/01/underarm-odor.jpg" alt="" width="425" height="282" srcset="https://blogcms.23andme.com/wp-content/uploads/2013/01/underarm-odor.jpg 425w, https://blogcms.23andme.com/wp-content/uploads/2013/01/underarm-odor-300x199.jpg 300w" sizes="auto, (max-width: 425px) 100vw, 425px" />
Here’s something to file under “Thank Goodness!” Researchers at the University of Bristol found that people with the genetic variant making them more prone to smelly armpits are also more likely to wear deodorant.
The paper, published in the <a href="https://www.nature.com/jid/journal/vaop/ncurrent/full/jid2012480a.html">Journal of Investigative Dermatology</a>, looked at variants in the ABCC11 gene that had previously been identified with what scientists describe as “axillary osmidrosis,” known to most people as underarm odor.
Individuals with a certain version of the single-nucleotide polymorphism (SNP) rs17822931 don’t produce as much sweat as other genotypes making conditions less ripe for underarm body odor. Ancestry also plays a role – a higher percentage of people with East Asian ancestry have this version of the SNP. Fewer people with European or African ancestry have this variant.
Since we’re talking about bodily functions we might as well mention that this same SNP is also associated with whether you have <a href="https://www.23andme.com/topics/traits/earwax-type/">wet or dry earwax</a>.
While these associations have to do with physical traits, what the researchers in Bristol were looking at was behavior. Specifically, they investigated if use deodorant depended on whether or not an individual had a genetic predisposition toward sweating.
What they found was not too surprising: if you have the genetic variant that is associated with more body odor you’re more likely to use deodorant.
But the study – which looked at more than 17,000 people – also found that behavior may be explained by cultural influences. For instance, while the percent of women who probably should use deodorant but choose not to was pretty small, a whopping 13 percent of the men in the same genetic boat don’t use deodorant when they probably should. Yikes.

Smells Like Gene Spirit

<img loading="lazy" decoding="async" class="alignright wp-image-4013 size-full" title="geneticresearch7" src="http://35.88.189.111/wp-content/uploads/2009/07/geneticresearch7.jpg" alt="" width="350" height="268" srcset="https://blogcms.23andme.com/wp-content/uploads/2009/07/geneticresearch7.jpg 350w, https://blogcms.23andme.com/wp-content/uploads/2009/07/geneticresearch7-300x230.jpg 300w" sizes="auto, (max-width: 350px) 100vw, 350px" />
Team 23andMe will again have a strong presence at the annual meeting of the American Society of Human Genetics.
We’ve been at this gathering of geneticists and those interested in human genetics ever since 23andMe launched, but this year with the 62nd annual meeting being held in San Francisco – sort of our backyard – we’ll be there en masse.
Each year the annual meeting attracts the best and brightest in human genetics with thought-provoking displays of research results and stimulating discussions. This year is no different and more than 6,000 people are expected to attend over the four days starting on November 6th.
Along with the 24 scientific sessions – including panel discussions featuring our Senior Director of Research Dr. Joanna Mountain, who will discuss research partnerships between academics and private companies, and Science Content Manager Dr. Shirley Wu, who will speak on the use of social media in research  – there are also 400 presentations drawn from abstracts submitted by scientists from around the world.
This year 23andMe submitted almost two dozen abstracts on a wide range of topics including our groundbreaking and first-ever genome-wide association study on sexual orientation, as well as preliminary findings from our<a href="../announcements/exomes-the-first-of-many/"> Exome Pilot</a>, which is the first exome sequencing offered directly to consumers. (We will link to these abstracts when they’re available on the ASHG website.)
Also reported in one of the abstracts are some of our findings from a full-genome sequencing project on 50 people with the LRRK2 G2019S mutation associated with Parkinson’s disease. We’ll also have details of a study that looks at an association with hypertrophic cardiomyopathy, the leading cause of sudden cardiac death in young athletes.
Being 23andMe we also have some less serious – but no less interesting – abstracts looking at such things as genetic associations with motion sickness, over 250 genetic associations with common traits such as baldness and unibrow, whether DNA can explain why some women get stretchmarks and others don’t, as well as why some people love cilantro and others think it tastes like soap.
We’re pretty excited by the upcoming conference.
We are particularly proud of our colleague, Dr. Uta Francke, who will deliver a presentation as recipient of the 2012 ASHG William Allan Award. As always the gathering will not just be a chance for us to present some of the interesting results from our research, but also to learn from others. There’s some fun stuff too, including a symposium on “Human Genetics in Contemporary Poetry, Fiction, and Art: How Humanists View our World,” and meeting will close with a forward looking symposium on the future of human genetics.
The preliminary 2012 Meeting schedule is now available. While we can’t wait for the meeting, we’re even more excited about sharing some of the interesting findings and breakthroughs we’ve made with the help of our customers. In the coming weeks we’ll collect information on all the 23andMe presentations onto a single web page so you can find them easily.
Stay tuned for more information about 23andMe’s presence at ASHG.
We’ll have a booth in the Exhibit Hall, and knowing our scientists, they’ll manage to squeeze a party in there too.

Highlighting 23andMe Research at ASHG 2012

<img loading="lazy" decoding="async" class="aligncenter wp-image-12215 size-full" title="marsalis-musical-ancestor" src="http://35.88.189.111/wp-content/uploads/2012/04/marsalis-musical-ancestor.png" alt="" width="504" height="280" srcset="https://blogcms.23andme.com/wp-content/uploads/2012/04/marsalis-musical-ancestor.png 504w, https://blogcms.23andme.com/wp-content/uploads/2012/04/marsalis-musical-ancestor-300x167.png 300w" sizes="auto, (max-width: 504px) 100vw, 504px" />&#8220;Musical Royalty&#8221;: <a href="http://video.pbs.org/video/2206762934">Watch the video</a> from the PBS series Finding Your Roots with Henry Louis Gates, Jr., as he speaks with Branford Marsalis about his relative Wellman Braud, a pioneering jazz bassist.
Just as jazz greats Harry Connick Jr. and Branford Marsalis wondered, in the first segment of the PBS series Finding Your Roots, whether they had musical ancestors, you too might wonder where you got your penchant for painting or your bright blue eyes.
Many traits, as you might imagine, are complicated – is someone a musician because of innate, and possibly genetic ability, or because of her environment? Are you outgoing or shy because of your genes, or because of how you grew up? In most cases it is likely a combination of both, but that may make it even more interesting to learn that your ancestors shared certain qualities you see in yourself, whether it be a special talent or a streak of stubbornness.
<h6>Family Traits</h6>
For some traits, it can be easy to see a resemblance. Many of us have gazed at old, faded photographs of our parents or grandparents (or more distant relatives, if we’re lucky!) in their younger years and marveled at how we can see ourselves in them. The connection can be something obvious, like wild unruly hair or a distinctive shape of the nose, or it can be as subtle as a smile.
Because of genetic discoveries, you can trace a few such traits through your DNA. Those bright blue eyes could be due to specific factors located in genes responsible for pigment, passed down through generations. Or, if you’re Asian, you might look around the table at family holidays and see the pink-flushed cheeks that accompany a glass of wine – also a trait known to have a genetic basis. Does your mother’s father have male-pattern baldness?
If you’re a man, chances are that you’ll inherit this trait as well.
<h6>Perfect Pitch</h6>
<img loading="lazy" decoding="async" class="alignright size-medium wp-image-12209" title="EyeColor" src="https://blog-api.23andme.com/wp-content/uploads/2012/04/EyeColor-300x116.png" alt="" width="300" height="116" srcset="https://blogcms.23andme.com/wp-content/uploads/2012/04/EyeColor-300x116.png 300w, https://blogcms.23andme.com/wp-content/uploads/2012/04/EyeColor.png 516w" sizes="auto, (max-width: 300px) 100vw, 300px" />If they carry one particular genetic variant, two individuals with brown eyes can have children with almost any color eyes.
Research on the specific musical ability called “perfect pitch” suggests that this ability to recognize and produce musical tones is the combination of innate potential and early training. But we don’t yet know which genes are involved.
Indeed, no one has discovered much about the genetics of traits like artistic ability or personality. Why hasn’t anyone figured these out yet? Researchers have certainly searched for genetic contributions to handedness, personality, and <a href="http://35.88.189.111/articles/rhythm-and-musical-traits">musical ability.</a>
But it may be that the genetic models we assumed in those studies were too simple.
<h6>Genetic Models</h6>
In one common type of genetic study, researchers compare two groups of people — those with a trait (say, perfect pitch) and those without. They step through a million or more genetic “markers” or positions throughout the genome, and ask at each step, “Do the people with perfect pitch have more of one version of this DNA marker than do the people without perfect pitch?”
This approach works well if many of the people with perfect pitch have the same genetic variant, and that variant influences the trait strongly. This doesn’t seem to be the case for many traits, however.
<h6>Bigger Studies</h6>
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<img loading="lazy" decoding="async" class="alignleft size-full wp-image-12163" title="small_23andMe_logo" src="https://blog-api.23andme.com/wp-content/uploads/2012/04/JRBgdIBXKIeVIdETJrxYIw_ttam_logo.jpg" alt="" width="24" height="40" />
23andMe customers can see what traits they and a potential partner might pass on to their children.
Not yet a customer? <a href="https://www.23andme.com/store">Visit our store</a> or learn more about the <a href="https://www.23andme.com">Personal Genome Service ®</a>.
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Two things will help researchers discover the genetic factors behind those traits we see shared in families. First, studies that include a very large number of people with and without a given trait will help us find common genetic factors that have even a small influence on the trait.
By involving tens of thousands of people in studies, researchers have recently discovered genetic variants that influence freckling, sneezing in bright sunlight, and whether or not someone has a sweet tooth.
<h6>More Genetic Data</h6>
Second, a trait such as the love of vinegar and lemons that you share with your cousin may be influenced by genetic variants that are unique to your extended family. In that case full genome sequencing – that is, examination of all 3 billion positions in the genomes of a few family members – would be needed to get to the bottom of the family mystery.
DNA can tell us a lot about our ancestors and where we came from, and it turns out that it can also tell us a bit about why we’re the way we are. Perhaps that trait you share with someone in your family tree comes from a little shared DNA.

Ancestral Traits

By Ann Turner, M.D.
Many members of my extended family have inherited a mutation responsible for hearing impairment.   The loss is detectable in childhood and progresses gradually over the years. I began wearing hearing aids forty years ago, when I was thirty.
<h6>A Search</h6>
We have participated in several genetic studies over the years, but the cause has not been found yet. I decided to see how far I could get by testing cousins with and without the hearing impairment. With testing could I at least identify a chromosomal region shared by just the relatives with the condition?
<div id="attachment_22394" style="width: 297px" class="wp-caption alignright"><img loading="lazy" decoding="async" aria-describedby="caption-attachment-22394" class="size-medium wp-image-22394" src="https://blog-api.23andme.com/wp-content/uploads/2015/04/Ann_cropped_modified-287x300.jpg" alt="" width="287" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2015/04/Ann_cropped_modified-287x300.jpg 287w, https://blogcms.23andme.com/wp-content/uploads/2015/04/Ann_cropped_modified.jpg 355w" sizes="auto, (max-width: 287px) 100vw, 287px" />Dr. Ann Turner, MD</div>
I began with myself and two cousins in 2007 when autosomal testing was first offered at deCODEme (at a cost of nearly $1000) and continued adding cousins and even spouses as the prices dropped more and more at 23andMe.
Using traditional genealogical techniques, we were able to track the trait back through almost 200 years to John Riley (born about 1813 in Stafford County, Virginia) or his wife Mary Ellen Bigger (born about 1810 in County Antrim, Ireland).
<h6>Hearing Loss</h6>
We knew from memories of older family members that one of their children, Eliza Jane, was very hard of hearing. A letter written in 1893 by Eliza Jane to her sister Allie survives, wherein she asks:
“Does your hearing fail you anny? [sic] George is quite bad.”
Her brother George was 47 at the time, and Allie was 40. Clearly they were anticipating a condition that “ran in the family,” even before the term genetics was coined. As it turned out, Allie was not affected, but another brother, James, had a more complicated history.
James’ hearing difficulties are documented in some Civil War pension application papers. After the war, James married, became a carpenter, and had six children. He died at the age of 57 after a fall from some scaffolding. A coworker had called a warning that the scaffold was not secure, but he did not hear. His widow then applied for a Civil War pension.
<h6><img loading="lazy" decoding="async" class="alignright wp-image-25696 size-medium" src="https://blog-api.23andme.com/wp-content/uploads/2012/04/Trait-Chromosome-Diagram-293x300.jpg" alt="" width="293" height="300" srcset="https://blogcms.23andme.com/wp-content/uploads/2012/04/Trait-Chromosome-Diagram-293x300.jpg 293w, https://blogcms.23andme.com/wp-content/uploads/2012/04/Trait-Chromosome-Diagram.jpg 699w" sizes="auto, (max-width: 293px) 100vw, 293px" />Disability</h6>
There was some dispute about whether his hearing loss was a pre-existing condition, or whether it was related to his service, during which he had contracted the measles, a known cause of sudden deafness. He wrote in his own disability pension application:
“I was out of my head, and when I came to my senses the comrades of my company were taking care of me in the camp, and I was totally deaf, and have been severely deaf in both ears ever since.”
He was discharged, and his commanding officer wrote:
“This man was slightly deaf at the time of his enlistment. About the middle of October he was attacked with the measles and since his recovery he has been unable to hear even the loudest command.”
James would have been 18 at the time he enlisted, so if the hearing loss was noticeable at that age, he probably had both a hereditary and environmental explanation for his deafness. Some of his children were also known to be hard of hearing at a young age, but none of his living descendants still carry the trait (nor do any descendants of George).
<h6>What about the Genetics?</h6>
Those were some of the examples of the hearing impairment that we were able to trace through paper records, but what about the genetics? Could we trace the hearing impairment trait through DNA?
The Family Inheritance: Advanced tool at 23andMe is an easy way to visualize the chromosomal regions shared by different relatives. The figure shows four of the people I tested. They share the hearing loss, come from different lines of descent, and are the most distantly related possible. (Closer cousins share so many segments that the target wouldn’t stand out.) The answer to my initial question is a resounding yes! Other extended families may be able to follow this model of collecting cousins, which I have also described in a column for the <a href="http://www.jogg.info/52/files/SatiableCuriosity.pdf">Journal of Genetic Genealogy</a>.
James Lupski has proposed the term “clan genomics” for this type of endeavor.
Now what? The sense of hearing is complex, with numerous genes affecting structures and functions. To date, 122 different loci (that is, general locations) have been <a href="https://www.ncbi.nlm.nih.gov/pubmed/22016077">associated with hearing loss</a>. The actual gene has been identified for only half of those. None of the locations overlap the section implicated in our family, so we are exploring virgin territory. We’ve reduced the possibilities from 3 billion bases and 20-some thousand genes to a mere 15,000,000 bases and 278 genes (many with unknown functions), but there’s still a ways to go.
It’s highly unlikely that any of the SNPs in our genotype data from 23andMe are actually responsible, since the chip design focuses on relatively common variants. Thus I am participating in the exome pilot project at 23andMe, which will completely sequence the coding regions of all genes and (if we’re lucky) may identify a novel mutation. There may be no suspicious variants, or there may be a superabundance of potential candidates, but that’s part of the adventure.
In the meantime, I am always on the lookout for even more distant cousins who might harbor the same mutation. Circumstantial evidence makes John Riley the more likely ancestor, but he is a brick wall in my genealogy.
If the mutation originated with him, we might be the only people in the world to shed light on yet another gene important for the sense of hearing. If he inherited it from an ancestor, there might be other lines of descent out there who share some DNA with us in that part of chromosome 15. Either outcome would be intriguing.
To be continued…
23andMe’s services are not a substitute for professional medical or diagnostic advice.  Always consult your physician for medical or diagnostic advice.
Ann Turner received her undergraduate degree in biology in 1964 and her M.D. from Stanford University in 1970. Her interest in genealogy began in midlife, when she read a family memoir about her father’s ancestors coming to America in 1635 on the ship Abigail. She began thumbing through the passenger manifest, where she recognized another familiar name–one of her mother’s ancestors. One family had headed for Connecticut and another for Vermont. Their descendants–her mother and father–met and married 300 years later in Iowa.
She founded the GENEALOGY-DNA mailing list at RootsWeb in the year 2000, the same week she received results from the first commercially available mtDNA test at Oxford Ancestors. She is the co-author (with Megan Smolenyak) of Trace Your Roots with DNA: Using Genetic Tests to Explore Your Family Tree and writes a regular column called ‘Satiable Curiosity for the Journal of Genetic Genealogy. She has consulted with Sorenson Molecular Genealogy Foundation and 23andMe.

Ann Turner

Tracking Down a Trait

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<td><img loading="lazy" decoding="async" class="alignright size-full wp-image-8313" title="asparagus" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/asparagus.png" alt="" width="60" height="60" /></td>
<td><img decoding="async" class="alignright size-full wp-image-8314" title="redhairfreckles" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/redhairfreckles.gif" alt="" height="60" /></td>
<td><img decoding="async" class="alignright size-full wp-image-8315" title="tongue-flip" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/tongue-flip.gif" alt="" height="60" /></td>
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<td><img decoding="async" class="alignright size-full wp-image-8316" title="hyperextension" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/hyperextension.gif" alt="" height="60" /></td>
<td><img decoding="async" class="alignright size-full wp-image-7844" title="cartoon-baldness" src="https://blog-api.23andme.com/wp-content/uploads/2010/11/cartoon-baldness.png" alt="" height="60" srcset="https://blogcms.23andme.com/wp-content/uploads/2010/11/cartoon-baldness.png 443w, https://blogcms.23andme.com/wp-content/uploads/2010/11/cartoon-baldness-300x272.png 300w" sizes="(max-width: 443px) 100vw, 443px" /></td>
<td><img loading="lazy" decoding="async" class="alignright size-full wp-image-8317" title="handedness" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/handedness.png" alt="" width="60" height="60" /></td>
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Do you have your father&#8217;s eyes or your mother&#8217;s curly hair?
Do you have trouble drinking milk, or flush when you drink alcohol?
Many traits such as eye color, alcohol flush, and the texture of your hair are determined&#8212;at least in part&#8212;by genetics. Learning about them also helps make genetics more real. We can observe many traits directly, compare them between people, and see how some of them are passed down through families.
But traits aren&#8217;t limited to things you can see. They include whether you can smell certain odors, the levels of hormones or other molecules circulating in your body, and even whether you&#8217;re more resistant or susceptible to infectious microbes. The circus of human traits can be wide, weird&#8212;and wildly wonderful.
With 23andMe&#8217;s Trait reports, you can get a glimpse into more than 40 different human traits influenced by genetic factors. While you can &#8220;verify&#8221; certain things about yourself using these reports, it&#8217;s important to keep in mind that genetics is rarely the whole story. Your environment, lifestyle, and personal and family history can play a major role in what foods you like, your cholesterol level, whether you contract an infectious disease, and how tall you are, to name just a few things.
So what do my genetics say about some of my traits?
<img decoding="async" class="alignright size-large wp-image-17348" style="border: 1px solid #ccc;" title="traits-list" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/traits-list-700x596.png" alt="" width="500" />
As I mentioned in the previous post about Drug Response, I do flush when I drink alcohol. This is because I have one copy of a variant that disrupts a gene called ALDH2, which is involved in breaking down a toxic byproduct of alcohol.
The disruptive variant is fairly common in East Asians, so it&#8217;s not surprising that I have it. My dad also has this variant and displays the alcohol flush trait, but my mom has two working copies of the gene. As luck would have it, my two brothers won the genetic lottery on that one&#8212;they got working copies from both parents!
Another trait that displays population-specific differences is Earwax Type. Most people don&#8217;t even know there are different types of earwax, but our ancestors probably all had wet earwax, and dry earwax arose later in northeast Asia, most likely due to a single variant in a gene called ABCC11. If you&#8217;re East Asian like I am, your earwax is probably the dry type (check!), but if you&#8217;re not, you probably have wet earwax.
Not all traits are determined by single genes like Alcohol Flush and Earwax Type. Many, like Eye Color and Hair Curl, are influenced by a number of genes, and 23andMe&#8217;s Trait reports may only provide information on a subset of them.
Other traits can be affected by non-genetic factors; <a href="https://www.23andme.com/health/Lactose-Intolerance/">Lactose Intolerance</a>, for example, can be partly or effectively compensated for by the types of bacteria you have in your gut (indeed, this is probably what&#8217;s happened in my case, for I used to be less tolerant of dairy products than I am now).
For these reasons, the results suggested by the reports may sometimes differ from your personal experience.
<img loading="lazy" decoding="async" class="alignleft size-full wp-image-8321" style="margin-right: 10px; margin-bottom: 5px;" title="eyecolor-table" src="https://blog-api.23andme.com/wp-content/uploads/2011/01/eyecolor-table.png" alt="" width="369" height="238" srcset="https://blogcms.23andme.com/wp-content/uploads/2011/01/eyecolor-table.png 461w, https://blogcms.23andme.com/wp-content/uploads/2011/01/eyecolor-table-300x194.png 300w" sizes="auto, (max-width: 369px) 100vw, 369px" />
A common example of this comes up with the Eye Color trait&#8212;the report may say &#8220;Likely Blue&#8221; but you might actually have brown eyes, or vice versa. The discrepancy stems from the fact that the genetic variant presented in the report is not the only variant that determines eye color. It does, however, give pretty good estimates: if you have two copies of the A version of the SNP (like I do), you have an 85% chance of having brown eyes and a 14% chance of having green eyes; if you have two copies of the G version, you have a 72% chance of having blue eyes and a 27% chance of green eyes.
One copy each of A and G gives you an intermediate probabilities of brown, green, or blue eyes. So while the report may say that you are likely to have brown, or blue, eyes, there is still a chance that you don&#8217;t! As more research uncovers additional variants that influence eye color, we may be able to update the report to improve the predictions.
All of our reports offer the curious individual an opportunity to learn more about the genetics&#8212;and non-genetic factors&#8212;underlying human health and traits, from the everyday to the bizarre. You might be amazed to discover that some people can smell a specific odor in their urine after eating <a href="https://www.23andme.com/health/asparagus-metabolite-detection/">asparagus</a> (or can&#8217;t smell it!) or that others <a href="https://www.23andme.com/health/photic-sneeze-reflex/">sneeze</a> whenever they go out into bright sunlight, a condition charmingly referred to as &#8220;ACHOO syndrome.&#8221; Or perhaps you&#8217;re more interested in learning about how your genetic variants might influence how you <a href="https://www.23andme.com/health/response-diet-exercise/">respond to different diets or exercise</a>. With traits, there&#8217;s always something for everyone!
<div>Curious about possible traits for your child? Or wonder what your chances were of having green eyes? Customers can use the <a href="https://www.23andme.com/you/inheritance/">Inheritance Calculator tool</a> to see offsprings’ probability for 6 common traits using different combinations of “parents.” (Note, you must be sharing genomes with someone to select him or her as a “parent” in Inheritance Calculator.)</div>
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Have some unique or favorite traits of your own? Customers can help contribute to <a href="https://www.23andme.com/research/">research</a> on the genetics of dozens of human traits by taking <a href="https://www.23andme.com/you/23andwe/surveys/">surveys</a> about footedness, handedness, physical features, and pigmentation, among others.
<div style="margin-top: 15px; margin-bottom: 15px; padding: 10px; border: 1px solid #ccc; background-color: #ffc;">More Health at 23andMe posts: 
 
<a href="https://blog.23andme.com/23andme-and-you/genetics-101/health-at-23andme-what-can-you-learn/" target="_self" rel="noopener noreferrer">Health at 23andMe: What Can You Learn?</a>(Carrier status for Inherited Conditions)When One Size Doesn&#8217;t Fit All &#8211; (the genetics of Drug Response)
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For a refresher course on genetics or help navigating the service, visit  <a href="https://www.23andme.com/gen101/genes/">Genetics 101</a> on our website, or see our  Frequently Asked Questions.
Check out our companion series,  <a href="https://blog.23andme.com/2010/09/16/ancestry-at-23andme-what-can-you-learn/">Ancestry at 23andMe</a>, and other articles in  <a href="https://blog.23andme.com/category/23andme-how-to/">23andMe How-To</a>.

Traits — Page 4

Spit And Tell

Smells Like Gene Spirit

Highlighting 23andMe Research at ASHG 2012

Ancestral Traits

Tracking Down a Trait

Health at 23andMe: The Circus of Human Traits

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