SNP Testing

Your Y-Chromosome contains two types of ancestral markers. 
 
1) Short Tandem Repeats (STRs) – which trace recent ancestry.  These STRs are the numeric values that you find on our results page.  Example: 13 – 24 – 15 

2) SNPs – document ancient ancestry.  SNPs are small “mistakes” that occur in DNA and are passed on to future generations. SNP mutations are rare. They happen at a rate of approximately one mutation every few hundred generations.  Each of us carry multiple SNP mutations within our Y-Chromosome.  Collectively, the SNPs form Haplogroups.

What is a Haplogroup?

Family Tree DNA defines a haplogroup as follows: “The haplogroups are the major branches on the Y chromosome tree, defined single nucleotide polymorphisms (SNPs), which have accumulated along different lineages as Y chromosomes are passed from father to son over many generations. All haplogroups ultimately descend from a single Y chromosome carried by a male that lived in the distant past. The topology of the Y chromosome tree can be reconstructed by typing mutations in different human populations – as more SNPs are discovered (e.g., M254), the structure of the tree changes. Originally, the Y Chromosome Consortium (YCC) arbitrarily defined 18 haplogroups (A-R), which represent the major divisions of human diversity based on Y chromosome SNPs. Currently there are 20 haplogroups (A-T). In turn, each of these major haplogroups has numbered subgroups, or subclades, that are named with alternating letters and numbers.”  Example: R1b1a2a1a1b4
 
Easy to follow visual depiction.

I like the simplicity of the site, https://www.23andme.com/gen101/snps.  If that doesn’t work for you…here’s an oversimplification for explaining how to interpret the haplogroup R1b1a2a1a1b4. 
A cluster of men known as ‘R’ went off on a trip.  A genetic mutation occurred to one of these men.  The R’s went straight and the man with the genetic mutation group went right, had sons of his own and they became known as ‘R1’.  The R1 group went straight for a while and another genetic mutation occurred.  This new group went off in a different direction and became labeled as ‘R1b’.  So, now you have three groups; R, R1 and R1b coexisting in and/or living in different areas.  Just think of this happening until you get to the 4 in R1b1a2a1a1b4. 
 
However, it doesn’t stop there.  Researchers continue to find more SNPs as technology continuously improves.  Through individual SNP testing, I have actually been able to refine my haplogroup even further.  My new haplogroup is R1b1a2a1a1b4h2a1 (notice the h2a1 at the end).  But, the FTDNA tree hasn’t been updated yet (I’ve been told that it’s coming later this year).  So, to keep up with the most current Y-Tree, I often refer to the ISOGG Y-Tree, http://www.isogg.org/tree.  FTDNA is using their own Y-Tree which is an interactive version of the current Y-Chromosome Consortium’s (YCC) phylogenetic tree and the Family Tree DNA Draft Y-chromosome tree. It can be found at http://ytree.ftdna.com.
 
Project Participation

So many of us started with the STR portion of the testing.  However, it’s very easy to want to understand more about the deeper ancestry.  DNA testing is getting close to telling us the physical location from where our most distant ancestors lived.  We’ve even had ancient Clan Grant stories confirmed through our project.  Consider yourself a pioneer.  Just by participating, you’ve given researchers access to raw data that helps to document the path of man from the beginning of history to the present. 
 
In order to validate the DNA of a particular lineage, you may need to enlist others within your family to participate.  I would remind you that discounted pricing rolls around periodically.  So, be patient. 
 
Remember that we’re here to help you if you’re considering additional testing.  If you feel confident about proceeding, you can follow the detailed steps below for ordering additional SNP tests.
1) Login at www.familytreedna.com
2) Click on the orange button “Order an Upgrade” (a new page will display)
3) Click on the orange button “Order an Advanced Test” (a new page will display)
4) In the “Test Type” drop down list, choose “SNP” – enter the SNP that you’d like order in the “Marker” field and then click on the “Find” button (a new page will display)
5) You should see this one SNP test…to the right of the test, click on the “Add” link
6) Click on the orange button “Next” (a new page will display)
7) Enter your credit card information or request the invoice option

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