Wednesday, November 6, 2013

Hacking Your Health Part II: Ancestry


This is a continuation of the blog post Hacking Your Health.  Previously, we focused on the health, disease and drug aspects of the genetic testing results received from 23andMe.  While the Ancestry portion of the test results doesn't really apply to "Biohacking" I would be remiss in not discussing the fascinating information you can learn about your genealogy.



Ancestry Results

There is a wealth of information available in the Ancestry half of the report.  The dashboard overview provides a snapshot of the highlights.  Here you can see: the percentage of your dominant ancestry, specific countries of ancestry based on surveys taken by others with similar DNA, the estimated percentage of Neanderthal DNA, number of genetic relatives with 23andMe profiles (close family, 2nd & 3rd cousins, 4th cousins and distant cousins) and Top Relative Surnames.  Famous relatives will also be displayed here (while none were listed in my profile, Jesse James appears to be my wife's distant relative)

Ancestry Composition

Personally, Ancestry Composition is one of the bigger draws of 23andMe.  I've always had a keen interest in history.  My Great Uncle has documented a significant amount of my maternal grandmother's line however, little documentation exists for the rest of my family. The results from 23andMe "reflect where your ancestors lived 500 years ago, before ocean-crossing ships and airplanes came on the scene."

There are three different "resolutions" to the results (global, regional and sub-regional).  At the top level, I am 99.8% European, 0.2% unassigned (this is not surprising).  Zooming in to the regional view the results are divided between Northern (40.4%), Eastern (12.9%), Southern (2.2%) and Nonspecific (44.3%) European.  As you can see a significant portion of my ancestry is "Nonspecific European".  Zooming in to the sub-regional view does not provide much more clarity:


This much "nonspecific" ancestry is not unexpected for such a densely populated region.  With that said, the "Ancestry Composition" estimates can be tuned.  By changing the setting to "Speculative" the results become more interesting however, the confidence threshold drops from 75% to 50%:


Beyond the analysis of genetic information, 23andMe encourages customers to complete questionnaires to provide further ancestry correlation.  By hovering over any of the regions and clicking the arrow you will be provided with the sample sizes used to determine the region (includes both 23andMe data and public studies).  In my case, comparative genetic information and survey results were taken from 5,041 people to determine my ancestry.  Clicking "Show Details" provides a breakdown of how the participants self-identified their heritage.


Maternal Line/Paternal Line

As a male I have both an X and a Y chromosome allowing me to review genetic lines from both parents. A downside of genetic testing is that females have two X chromosomes which only provides the maternal line.  On the bright side there is an option to share data with others and by linking with male family members it is possible to have a more complete profile.

Both "lines" provide the haplogroup to which you belong as well as a heatmap of the haplogroups' distribution approximately 500 years ago (before the era of intercontinental travel).

My Maternal Line
My Paternal Line
The results also provide some facts about your haplogroups such as age (how many years the haplogroup has existed), region, example populations and a "highlight" (for instance one of my haplogroups appears to have been common in Doggerland).

23andMe provides additional information in another tab with a detailed history of your haplogroups and related subgroups.  A haplogroup tree is contained in its own tab where you can collapse and expand the different groups and highlight groups based on geographic location.


Neanderthal Ancestry 

This is a relatively new section.  Only in recent years was it discovered that modern day Homo sapiens sapiens share genetic code with Neanderthals (Homo sapiens neanderthalensis).  It's unclear exactly what this means from a genetic standpoint and 23andMe states, "There are many intriguing theories about what traits the smidgen of Neanderthal DNA may have imparted on modern humans, but we don't know yet if having a little more than average Neanderthal DNA could explain why someone is extra brawny, short or boorish.  Those traits might just be regular human characteristics."  The DNA for an average person of European descent is estimated to contain 2.6% Neanderthal DNA.


DNA Relatives 

This section is broken up into three tabs, List View, Map View and Surname View.

List View:  This is quite literally a list of all 23andMe users who are genetic relatives.  Users are able to share as much or as little information as they would like. This ranges from virtually nothing to names with complete profiles (examples below):

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Map View:  Genetic relatives are pinpointed on a a Google map.  Links are provided to quickly zoom to specific regions or to "Top Locations" (highest concentration of genetic relatives).  Almost half of my genetic relatives currently reside in the United States:

Click to enlarge
Surname View:  This view lists the frequency in which a last name appears among your genetic relatives. Actual counts are provided as well as an "enrichment" number which indicates "how common a particular surname is among your Relative Finder matches, compared to the entire 23andMe database."

Click to enlarge

Ancestry Tools 

Ancestry Tools are listed as features that "may still be in development, require specialized knowledge or appeal to only some [23andMe] customers."

Countries of Ancestry:  This feature combines information from Relative Finder matches and those matches' answers to the "Where Are You From?" ancestry survey.

DNA Melody:  This was a delightfully unexpected bonus.  23andMe maps specific traits in your profile to the rhythm, pitch, key and timber of a melody.  Click to "hear" my DNA.

Family Inheritance  Advanced:  This tool allows you to compare your DNA, bit by bit, to see what segments you share with close and distant family.  With this tool you can "find out where those DNA segments start and end, and see how DNA is transmitted across multiple generations by comparing multiple family members against a person in question."

Global Similarity Map:  This feature provides migration animation that "shows who in the world you most resemble genetically" over the last 50,000 years.

Haplogroup Tree Mutation Mapper:  This feature shows you which particular mutations in a person's mitochondrial DNA (maternal ancestry) or Y chromosome (paternal ancestry) were used to determine their haplogroup assignment.


Overall 23andMe provides a remarkable amount of information at a relatively low cost.  If you are interested in obtaining your own results I invite you to use this referral link:
http://refer.23andme.com/v2/share/6224967130210323244