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Transcript of Autosomal DNA
-give you more detailed information about the autosomal DNA testing procedure
-provide you with detailed information about each of the four major autosomal DNA testing companies
-help you understand what DNA testing can, and cannot do to help you in your genealogy
-produce in you a greater curiosity for all things DNA and genealogy (we hope!) Background Autosomal DNA (atDNA) is the latest genetic tool available to genealogists. It has the potential to change the way we conduct genealogical research using DNA testing. However, it can also create considerable confusion. This CD is meant to bridge the gap between the scientific jargon and the information you really need to move forward with your genealogical work. Ready? Set. GO!!! In humans, "autosomal DNA" refers to the 22 pairs of chromosomes that are found in the nucleus of almost every cell in your body. This is the DNA that can be used to uniquely identify you among all the millions of people in the world. Inheritance Each of our parents contributed half of our autosomal DNA. Which is different from YDNA and mtDNA which follow a single line of inheritance (AKA uniparental markers). The data received for each test is very different, as are the interpretation tools. What atDNA is tested? The most common testing is done using Single Nucleotide Polymorphisms (say that three times fast!).
They are called "SNPs" for short (pronounced "snips"). In fact... Testing companies test anywhere from 200,000 to 900,000 SNPs, or more, of your DNA to create a detailed autosomal profile of your genome. DNA is made up of four different building blocks known for simplicity purposes as A, T, C, and G. A SNP occurs when one building block, say a "C", changes to another, perhaps a "G". What is a SNP? For example, in YDNA, haplogroup K is a deep deep ancestral group, identified by a SNP called M9, whose estimated age is 47,000 years. Based on the geographic distribution and frequency of this particular genetic marker, scientists believe M9 arose in South or West Asia. A Genetic Journey Think of this signpost positioned in Southwest Asia. Everyone standing at this post has the M9 SNP in their DNA. Given another 10,000 years, many with the M9 SNP have now moved on to one of five main locations.
Perhaps they decided to head east, and became part of haplogroup M, defined by SNP P256. Or maybe they headed south and settled in Papua New Guinea, and with time developed their own exclusive SNP, M230, that defines haplogroup S.
Or it is possible they headed off in an entirely new direction, following haplogroups L and T to populate India, Iran, Pakistan, or Egypt. Guessing Ages While it is never polite to guess a lady's age, scientists can determine the age of a SNP based on how many individuals in a given population carry that SNP, among other things. The more people with a particular SNP, the older that SNP must be. Autosomal DNA SNPs atDNA SNPs work in a similar fashion to provide the genealogist with two valuable, source of information: Ethnic Background Which gives you information about your deep ancestral heritage, back in time 500 years or more. Genetic Relationships Identifying individuals with whom you share recent common ancestry, as far back as 6 generations (at least for the time being). Most testing companies provide both types of information to you within the same test. Ethnic Background Sometimes referred to as an Admixture Analysis or Biogeographical Statistics. Many genealogists eagerly await atDNA test results to discover what their DNA can tell them about the geographic origins of their ancestors. Testing Companies As you may already know, YDNA follows your direct paternal line and it is shared with all your male relatives on your father's side. MtDNA is found on the opposite side of the tree, following an unbroken maternal line. mtDNA Data YDNA Data atDNA Data and this is just a tiny bit of the data you can receive from an atDNA test Oh no!! Not NUMBERS!! It's OK, don't fret, just take a quick look. Knowing the age of a SNP is helpful in identifying the point in history when a genetic lineage diverged from another. Four major players are offering atDNA testing for genealogical purposes at the present time: All companies offer variations of both kinds of DNA test results (do you remember what they are?) Let's go over some basics about these types of information before discussing the different tests offered by each company. Ethnic Background information and Genetic Relationship matching.* *Geno2.0 provides primarily the Ethnic Background information, though there are some relationship matching options when you test with them. Origins are a tricky thing to talk about, as different groups of scientists may define the same geographic regions or populations differently.
Ultimately, the quality of the data presented to you depends heavily on the database of information each company has available to compare your atDNA against. These databases are a work in progress and will continue to expand over time. For example, this is the Ethnicity breakdown from 23andMe in its early years (circa 2007). But in November of 2012, it underwent an impressive makeover! General Take Home Message About atDNA Ethnicity Breakdowns: Be careful. While each company has done their best to ensure that their reference populations are specific and indigenous, while still being diverse enough to provide a decent cross section of people. Whew! That is a tall order. And, as you might have guessed, they sometimes fall short. I am from WHERE?! The tricky thing about Admixture results is that they really have two very different components: Time and Place You may have a SNP that arose in the Middle East 25,000 years ago, but it is still found in you today, regardless of the part of the modern world where you reside. For the most part, your current admixture results are reflecting the ancient locations of origin for your ancestors, and not necessarily the more recent components of your ancestry. YDNA YDNA YDNA YDNA YDNA However, scientists are continually working to resolve the time and place issues associated with finding groups of SNPs that may have originated at different locations, even if they are found elsewhere in more modern populations. Think of the SNP time and place problem like the produce section of an average grocery store in the United States.
If you see a mango, it was likely not grown locally, but in South America, perhaps Brazil. If that Brazilian mango was a SNP and it was detected in your DNA, we might be tempted to say that you are Brazilian. This is partially true and your ancient origins may have included Brazil, but your genetic past can only partially contribute to define who you really are. People should be careful about defining individuals based on the presence or absence of genetic markers that arose thousands of years ago around the globe. There is much more to a person's culture and background than a genetic test. The challenge for scientists today is to look not just at one SNP, (like a single mango), but at the full genetic picture, like the oranges, bananas and grapefruit found with the mango. They are found together in a single grocery store, but they came from many different places before finding their way in a single place. Likewise, each person has many SNPs that came together in a single place (YOU) from ancestors that came from a number of different areas around the world. Reference Populations Which brings us to our next point when dealing with Ethnicity results: Knowing the population groups that were surveyed to create the database used to compare your data is very very important.
Every testing company tries to clearly explain what reference population is used in order for you to evaluate your results correctly, but not every company uses the same reference population.
Here are two examples of European reference populations: FTDNA 23andMe Admixture Results Recap: Two important tips in understanding Admixture results: SNPs have a time and a place Know your reference populations Genetic Relationships Remember, in addition to your Admixture Results, you also receive an analysis of your based on the testing company's database of customers These relationship estimates range the present time from brother/sister/mom/dad to 5th / 6th cousins. In general, there are two reasons you will be told you share a recent relationship with another individual: You actually DO share a common ancestor in the time frame provided. Testing companies give us some guidelines as to what we can expect from them in predicting our relationships to various individuals. The percentage shown tells us how often they are able to correctly identify each relationship: Second (or closer) cousin: 99%
Third cousin: 90%
Fourth cousin: 50%
Fifth cousin: 10% You simply share common geographic origins If you do not share a common ancestor, you might be told that you do because: Unfortunately, you won't know for sure until you do a little digging. Now that we have reviewed the basics of Admixture and Genetic Relationships let's review each testing company individually. Analysis 23andMe Company Profile 23andMe Privately held company based in California.
Founded in April of 2006.
Their goal is to help individuals "gain deeper insights into personal ancestry, genealogy and inherited traits."
http://www.23andMe.com Admixture Analysis at 23andMe The Admixture tool at 23andMe excels both in its presentation and content. It also contains valuable analysis tools for the genetic genealogist to make the most of the data provided. Admixture Tool Summary Ease of use
Several data viewing options
Specific reference populations give you detailed information about your ancestry Genetic Relationships 23andMe provides tools for you to collaborate with others who have a similar genetic make up in order to verify or extend your genealogy. Advanced Relationship Tools 23andMe also offers a few tools for deeper analysis of your relationships with others.
By identifying the specific segment of shared DNA you may be able to shed further light on your relationship with another individual. Relative Finder Summary 23andMe provides a wide range of tools with which to analyze your DNA matches.
Please note that many of the individuals tested by 23andMe may have signed up primarily for the health information and may not know much about their ancestry. Health Information at 23andMe 23andMe does provide information regarding various aspects of your health, including:
Your predisposition to various ailments and diseases including breast cancer and Alhzeimers.
Your sensitivity to certain drugs.
Anecdotal information (traits) like the wetness of your earwax and your preference for cilantro. How much does it cost? 23andMe has the lowest priced test at $99 You can also download your raw data and transfer your 23andMe results to FTDNA.com for only $89, giving you many of the benefits of both databases for a relatively low price.
23andMe does not currently accept data from other companies. FTDNA FTDNA Company Profile Family Tree DNA is a genetic genealogy company founded in 1999 by genetic genealogy pioneer Bennet Greenspan.
Based in Houston, Texas.
They have an extensive customer base and offer YDNA and mtDNA testing in addition to their autosomal DNA test.
http://www.ftdna.com Admixture Tool at FTDNA Population Finder The population finder tool at FTDNA allows you to explore your deep ancestral origins.
It is important to review the populations used as the reference populations to better understand the results you see. Link: http://www.familytreedna.com/faq/answers/default.aspx?faqid=22#1039 Population Finder Summary The population finder tool can be useful for those who have general questions regarding their ancestry with regard to large population groups.
For example, Population Finder could help you identify your African or Native American roots. Family Finder Genetic Relationships FTDNA The Family Finder tool was created with the genetic genealogist in mind. Top Features:
Relationship estimates from close and immediate relatives to 6th cousins.
View the amount of DNA shared, in a measurement called centiMorgans (cM).
If you upload your genealogy as a Gedcom file, FTDNA will highlight the surnames you have in common with your matches. Advanced Tools Family Finder Family Finder Summary Family Finder provides an array of both simple and complex tools for analyzing genetic relationships.
They also allow you to download your raw data (a feature shared with other companies providing atDNA testing) for use in third-party applications (more on that later!!). How much is it? Family Finder Test $289 FTDNA also hosts data from other testing companies. For example, you could transfer your data from 23andMe for only $89, or you can upload your data from the National Genographic Project (GENO 2.0 test) for FREE. Ancestry Ancestry DNA Company Profile AncestryDNA is a division of Ancestry.com, the well-known and publicly traded genealogy company.
Ancestry.com began their foray into DNA testing in 2002 offering mtDNA and YDNA testing.
Their autosomal DNA product was launched in May of 2012. Admixture Analysis AncestryDNA As of March 2013, AncestryDNA is still in the Beta stage of its autosomal DNA service.
Highlights for the Admixture portion:
they are using 22 reference population groups
they provide tools to analyze how your current genealogical knowledge interacts with the genetic findings
you can see how the ethnicities of your matches compare to your own AncestryDNA Genetic Relationships As you might expect from a genealogy company, AncestryDNA has worked hard to try to help you make solid genealogical connections with your matches.
You can view your match's family tree, you can see a list of surnames in their family tree, with the shared names between your trees highlighted.
Ancestry.com members will also see the familiar shaky leaf providing hints to relationships with matching members. As of March 2013, Ancestry.com does not provide additional genetic analysis tools or the ability to download your raw data file. But this is likely a limitation of the Beta version, and will likely change in the future.
Ancestry.com is also the repository of the large Sorenson Molecular Genealogy Foundation genetic genealogy data collection, as well as SMGF YDNA and mtDNA databases (www.SMGF.org). How much does it cost? AncestryDNA test is $199 non-members $129 Ancestry.com members Geno2.0 Company Profile Geno2.0 Geno2.0 is a product from the National Geographic's Genographic Project whose goal is to "better understand our human genetic roots."
The Genographic Project was launched in 2005 testing YDNA and mtDNA. Geno2.0, the autosomal component of the study, was launched in October of 2012. https://genographic.nationalgeographic.com Admixture Analysis Geno2.0 While the Geno2.0 test evaluates only 150,000 SNPs, compared to the 700-900,000 offered elsewhere, keep in mind that each of the 150,000 was carefully selected for two main reasons: Their value in determining population origins
Their uselessness for anything else (e.g. they won't provide any health information) YDNA Haplogroups Geno2.0 One of Geno2.0's most useful features for genetic genealogists is the fact that they test 12,000 YDNA SNPs, many of which have only recently been discovered.
This allows many men to fully identify their YDNA haplogroup, where before they only had a prediction, or a relatively distant haplogroup assignment. For example: After completing a YDNA test at Ancestry.com or FTDNA a gentleman was told he was in haplogroup R1b-M269, which extended naming is: R1b1a2a After the Geno2.0 test hewas able to learn that he was part of haplogroup R1b-DF25, also known as: R1b1a2a1a1b3a7b1 Quite an improvement in the resolution of YDNA haplogroups with the Geno2.0 test. How much does it cost? Geno2.0 test is $199.95 3rd Party Third Party Analysis There are additional tools that have been developed to analyze the raw data provided by the testing companies outlined in this presentation.
These analysis are a little more complex to understand due to their scientific nature, but they are certainly worth a look.
To use these tools you will need to download your raw data from either 23andMe, Geno2.0, or FTDNA (and probably soon from AncestryDNA). Top Two Third Party Tools Interpretome A tool produced t by researchers at Stanford University. http://esquilax.stanford.edu/#painting (Go to Ancestry-Painting-HapMap3) GedMatch Created by genetic genealogists, this tool allows you to explore both your Admixture results as well as finding Genetic Relatives who may have been tested at a different company. http://gedmatch.com Genetic Genealogy Consultant Need More Help? We create personalized reports to help you understand how your genetics relates to your genealogy. http://GeneticGenealogyConsultant.com GeneticGenealogyConsultant@gmail.com Autosomal DNA does not include the "sex chromosomes" found on the 23rd pair (XX in women and XY in men) and does not include mitochondrial DNA (mtDNA) found outside the nucleus. However, many testing companies include this DNA in their atDNA tests. mtDNA and YDNA 23andMe does test locations on the YDNA as well as some of the mtDNA. If you are male, along with your atDNA results you will also receive a haplogroup, or deep ancestral group, determination for both your direct paternal (YDNA) and direct maternal (mtDNA) line. Females will recieve only thier mtDNA line (as females do not have YDNA).