Friday, October 10, 2014

NextGen Sequencing and yDNA: Part 2


This post is a continuation of my post two days ago.

Within the last week several events have occurred to flesh out our small project. This is exciting but it also will take a while to absorb this influx of new data and make sense out of it all. However, relationships are emerging among project members -- some of whom had previously appeared to be living alone on almost deserted ySNP islands.



The results of an additional BIG Y kit has come back. This connected two men with at least several recent generations of documented French descent. Although they still may not have a common ancestor in genealogical times, their match appears to be within the last millennium. For one of these men whose father was adopted, this is encouragement that he is on the right track in pursuing some ySTR matches who are also of French ancestry.

One member has received Sanger confirmation through ySeq that his S1026 result from NextGen sequencing was correct. Although this analogy is very crude, NextGen sequencing is the equivalent to taking images from a space satellite. On the other hand, Sanger technology would be like driving to a specific location on earth and recording an image. 

NextGen sequencing is much faster for scanning large areas particularly those which may be almost inaccessible or those which have coordinates which were previously inexact or even unknown. It is great for discovery. 

On the other hand Sanger technology can be targeted precisely to one specific location (SNP or STR) and is considered to be much more reliable. The down side it is much more expensive drive around on the surface of our genomes and record a series of images that could be stitched together to form a coherent map. It is much faster and cost effective to start with satellite images. 

Two men who previously had close ySTR matches with others who had previous BIG Y results have tested a single downstream SNP through Sanger technology through FTDNA and confirmed they belong in this project. These men were able to target a specific SNP that had been identified by the BIG Y results of someone with whom STR results had previously suggested a distant relationship did exist. Thus at the cost of a single SNP test, these two men were able to confirm that their SNP trail takes time down into historical times and perhaps to the beginning of the genealogical era. 

One project member got this week, after a wait of three and a half months, his Chromo2 results from ScotlandsDNA. The early examination of the results confirmed that he did belong to R1b-S1026. It was in fact this test that identified and named a SNP at location 19201991 as being S1026. That is where the "S" came from in the naming protocol.

All of these results coming back within the same week has energized our tiny project which now only has a baker's dozen of confirmed members. However, it will take us a while to puzzle over what it all means and what our next steps should be to continue to trace our diverging trails down into genealogical time and hopefully connect with the documented genealogies of specific families.  

But now I must tear myself away from all this and fly to Houston today for Family Tree DNA's 10th Annual Conference on Genetic Genealogy. Don't you just hate it when your opportunities to learn more about genetic genealogy compete for your time to actually do genetic genealogy? I know, I know. I should just be grateful for my opportunities. And I am. 

No comments:

Post a Comment