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Author Topic: Genetic Genealogy  (Read 26303 times)
dadams
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« on: June 08, 2009, 11:14:52 PM »

I suppose this fits in the searching for section as I was essentially searching for information. This info may be of interest to others who also may be at a roadblock in their own search.

In an effort to compensate for the lack of heritage and knowledge of my genetic father I undertook a genetic genealogy test from Family Tree DNA. While there are numerous companies offering such services, FTDNA was settled on due to having the largest database, a factor of great importance when trying to create a match with a potential distant relative. Once the testing kit arrived in the letter box it was a simple matter of collecting some buccal cells (cheek cells from the inside of you mouth) via a scraping, then sending it back to the testing company and waiting for the results.
The genetic genealogy test in regards to paternity works by following the Y-chromosome through the generations, as such, finding more information on your genetic donor father and your heritage through that part of your family tree is only possible for male offspring. Unfortunately female offspring are unable to do this. However, if they are a product of donated eggs they (as well as male offspring) could potentially follow the maternal side of their family tree through mitochondrial DNA testing which follows the maternal line. Both tests implement the premise that both the Y-chromosome and mitochondrial DNA are highly conserved and do not change when passed onto the next generation. Small changes do occur occasionally due to mutations and is the reason why we can then see who is closely related to each other through their DNA and why most people are related to each other if we go back far enough in history. 
I purchased the Y-DNA 37 markers test from the option of 12, 37 and 67 markers on the recommendation of FTDNA with the theory being that 12 markers are not specific enough to verify a relation whereas 67 were supposedly too specific and that a certain degree of ambiguity is desirable when a person has no knowledge of their heritage or a genetically inherited family name (eg. adoptees and donor conceived).
These markers are assigned DYS (DNA Y-chromosome segment) numbers and a numerical value is returned based on which mutation has been detected in the test by looking for Y-STRs (short tandem repeats). It is these numbers which are used to match yourself with others that are related. From my results, FTDNA matched me perfectly to 4 other individuals at the 12 marker level, and to 2 others at a genetic distance of 2 at the 25 marker level. The genetic distance is a measure of how many markers are different and by what degree they are different. This was within the FTDNA database, however, it is possible to put you values into a wider database such as Y-SEARCH which allows people who have been tested by other companies to put their values online and to search for matches. The advantage of a database such as this is that it can be considerably larger and it allows you to conduct more thorough searches by changing the parameters to which matches are made which is not possible on the FTDNA site and subsequently, people that can be related could be excluded from being shown to you through the FTDNA results. Putting my marker values in Y-SEARCH allowed me to match to several individuals at more than 30 markers with a relatively small genetic distance. While it may at one level be beneficial to keep some level of ambiguity in your testing for those of unknown paternity. It can also create other problems in that by not being specific enough to confirm a close relation. From 37 marker results it is possible that someone that may appear close is actually quite distant at the 67 marker level, and conversely someone who may not initially appear as the main person of interest at 37 markers may be considerably close at the 67 marker level.
In addition to the marker values and possible matches that are obtained through such testing, a haplogroup can be assigned to your results. This haplogroup basically describes a part of the population that originates from a common ancestor through the use of single nucleotide polymorphisms (SNPs). As such depending on what haplogroup may be assigned to you, the region from which your paternal line comes from can be pinpointed or narrowed down. For example my haplogroup is most closely associated with the British Isles and Western Europe. This haplogroup can be defined to a greater level through Deep Clade testing which then has the possibility of further refining your ancestral origins to a region within these areas. My haplogroup assignment is also supported by the greatest number of matches I had of certain markers which define recent common ancestor origins to the areas of England, Scotland, Ireland and Germany.
So how do these results affect my knowledge of my heritage and my quest to find my genetic father?
In several ways;
First the matches that I have been able to make provide a basis to conduct further research. For those in the databases that have selected to allow their contact details to be accessible, they can be contacted and research can be conducted on their family history to see if there is a possibility of a closer link.
Secondly, the surnames (and their derivatives) that can come back as matches can be used by donor offspring to cross-reference with in my case names of medical and science graduates which comprised the donor pool at that time as possible avenues of enquiry.
Thirdly, any haplogroup assignment could also help narrow down the name pool of potential donors from the aforementioned donor pool based on certain family names originating from certain areas of the world.
The use of such testing has been used successfully previously with one donor offspring in the USA finding their genetic father by matching up with a close relative. There are also other companies which conduct health analysis of DNA. These tests analyse a person’s potential susceptibility to certain illnesses based on genetic links with these diseases.
The thing that must be noted is that any genetic genealogy result obtained is dependent on a close or distant relation also having undergone testing. While currently the greatest population of people undergoing such testing live in the USA, the British Isles and Western Europe, with more and more people being tested everyday, for those that may not get closer to discovering their heritage or even their paternity initially, eventually they may get there given time.
While I cannot show here the results of any matches as enquiries are ongoing, they have not excluded any of the information and lines of enquiry that I had obtained through other means before undergoing genetic testing. In regard to further genetic testing I may in the near future increase the number of markers to narrow down some of the potential matches if the line of enquiry deems that it would be of benefit. A further refinement of the haplogroup assignment by Deep Clade testing may also assist in this and will be assessed on its necessity as required. A full DNA “health” analysis is something that I will undertake to fill in the gaps of a family health history that I am missing. While genetic genealogy testing and DNA health analysis may not give to me the genetic father that has been missing in my life, it has the potential to provide for not just myself but also to my children a picture of our heritage (the origin of my paternity by region) but also a family health history which will be just as important to them as me.     
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Quinny
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« Reply #1 on: June 09, 2009, 01:14:55 PM »

Thanks for that Damian.

I have often looked at those genetic testing websites and wondered whether it was worth joining. I think I will give it a go and go with the highest level marker I can. Smiley
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dadams
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« Reply #2 on: June 09, 2009, 10:31:58 PM »

Hi Adam

good luck, if you have any specific questions please feel free to ask on here or email me.

Regards
Damian
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Quinny
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« Reply #3 on: November 19, 2009, 02:42:44 PM »

I've just ordered the Y-DNA67 test from http://www.familytreedna.com.

I will be interested to see if there are even any approximate matches on the ysearch database.
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Donor conceived adult from Perth, Western Australia. Searching for a donor who donated to Dr Colin Douglas-Smith in 1976.
dadams
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« Reply #4 on: November 23, 2009, 05:23:52 AM »

Hi Adam

will be interesting to see your results.
There are other databases as well such as ybase. So there are lots of places to search for potential matches.

cheers
Damian
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Quinny
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« Reply #5 on: December 13, 2009, 11:42:03 PM »

I have received confirmation that they got my DNA. Now I have to wait a few weeks for them to run tests. Hopefully I will have some results in January 2010.
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dadams
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« Reply #6 on: December 14, 2009, 10:33:46 AM »

Thanks for the update Adam.
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Quinny
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« Reply #7 on: January 14, 2010, 12:31:46 PM »

I have all my results now. Got 2 perfect matches at 25 markers.

At 37 marker level there are 9 men with a genetic difference of 4. One of them is also on the perfect 25 marker list.

No matches at 67 markers.

Will start searching ysearch and ybase soon.
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dadams
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« Reply #8 on: January 14, 2010, 09:30:36 PM »

Wow and I was just thinking this morning whether or not you had your results yet, and here they are.
That's great that you have 2 perfect matches at 25.
My closest at 25 has a GD of 2. So you are better off than me in that regard.
As you can see though that what happens at 25 does not necessarily correlate to what happens at 37. Eg someone who is close at 25 may not be at 37 and vice-versa (one of those who is a GD of 4 at 37 might have all of those 4 differences in the 25 marker bracket).
Uploading to ysearch can be done automatically through your Family Tree account. It is definitely worthwhile searching through there.
Did they give you a predicted haplogroup assignment? If not you can run an online prediction. While it is not definitive it gives a good overall picture (mine was fairly accurate but doing the deep clade testing gave much better resolution).
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Quinny
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« Reply #9 on: January 27, 2010, 01:39:19 AM »

I joined a heap of DNA search websites last night. I can't remember them all now, but it included ancestry.com and ybase.
Family tree DNA still had the best results for me.

I also realised that with all of the matches I have at 37 markers, only one of them has done as 67 marker test, so it is possible that I may match one of the 37 marker people at 67 markers too, if they would take that test.

This also applies to people who I match with at 12 and 25 markers who have not done further tests.

dadams, my haplogroup is a very common one from western Europe, which is basically what I expected and I know my Mum's family is from there too.
I haven't bothered to go further with it as I don't see the point.
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dadams
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« Reply #10 on: January 27, 2010, 03:16:31 AM »

Hi Adam,

based on my 37 marker test FTDNA suggested that my haplogroup was:
R1b1b2 (M169)
However after deep clade testing they were able to resolve it down to:
R1b1b2a1b5 L21 (M198)
So as you can see the result can change a little.
For matches you also need to belong to the same haplogroup as it can be possible to have high level matches from a different haplogroup, so they must be excluded.
However, just as you have seen with the marker tests (not everyone gets the larger markers done), the same is particularly true for haplogroups (deep clade testing).

Cheers
Damian
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Quinny
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« Reply #11 on: January 28, 2010, 06:04:39 AM »

Hi Damian,

Hypothetically, are you saying that if someone deep clade tested to R1b1b2 and you have have R1b1b2a1b5, even though you match a lot at 67 markers, you may not be related?

I thought the markers were the important requirement.

Cheers,
Adam
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Donor conceived adult from Perth, Western Australia. Searching for a donor who donated to Dr Colin Douglas-Smith in 1976.
dadams
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« Reply #12 on: January 28, 2010, 10:00:27 PM »

Both are important.
It is possible to be a perfect match with someone at 67 markers but not be related.
You can end up at the same markers from a different starting point - it is called convergence.
Markers on their own are usually good enough for people that can trace their family name (it is verifiable - hopefully no adultery going on). And then you would try and match with others with either the same name or derivatives there of.
As we have no name to follow our job is made more difficult (although sometimes medical student records can give us a clue).
If you match with someone closely at 67 markers, then haplogroups well help remove any of these false positives.
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Quinny
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« Reply #13 on: April 29, 2010, 12:51:03 AM »

I ordered the deep clade test and they have been testing for over a month now, so I guess this test takes a while. (Edit: I noticed the expected test end date is 17-May-2010).

However, when I checked the website I noticed this new test available:

-----------------------------
Family Finder

The next revolution in genetic genealogy
The science is simple - linked blocks of DNA across the 22 autosomal chromosomes are matched between two people. The degree of matching yields evidence for the relationship. You have exciting opportunities!

Match with five generations of family
With the Family Finder test you may extend the power of genetic genealogy to all of your ancestors. You can discover connections to descendants of all sixteen of your great-great-grandparents!

With our autosomal Family Finder test you may extend the power of genetic genealogy to all of your ancestors. Using a test of your own DNA, you can discover connections to descendants of all sixteen of your great-great-grandparents! The Family Finder test will not only open avenues for traditional research but will help you discover the hidden connections that could explain your family's migrations.

Adoptees discover their heritage
With the power of an autosomal DNA test, confidently match to male and female cousins from any of your family lines. This can provide you with the clues you need to learn more about your birth parents' families.

The possibilities abound!

  • Discover Parents, Grandparents, Aunts and Uncles.
  • Find Half Siblings
  • Make contact with 1st, 2nd, 3rd, and 4th cousins.


Every adopted person, or those who know that one of their parents or grandparents was adopted, will want to order a Family Finder test to help identify close and distant relatives.
« Last Edit: April 29, 2010, 12:59:50 AM by Quinny » Logged

Donor conceived adult from Perth, Western Australia. Searching for a donor who donated to Dr Colin Douglas-Smith in 1976.
dadams
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« Reply #14 on: April 29, 2010, 09:20:54 PM »

Someone else asked me about this and here was my response for what it is worth which isn't much.
But the deep clade test gets done at a different lab so they have to ship one of your samples interstate in the US which is why it takes a fair bit longer. It also depends on how many tests are currently being done and when you fit in with one of the runs.
I purchased a y-67 upgrade in march and the result is not expected until late may, so I guess they are getting busier. Which is good for them and good for us.
Anyway here it is:
Family Tree's family finder is VERY new. Now some people have taken it and have reported 5th and 4th cousins already. Seeing that it is so new that may be a little bit of a concern. So it will be interesting to see how it unfolds over the coming months and years.
However, many companies are now offering such a service so it is not a novel thing just to one company.
If I was to have a choice between a match using y-chromosome and autosomal it would be y-chromosome every day of the week.
Would I recommend getting one? It depends on what you expect out of it.
It might be possible that in the future (I doubt in the immediate time frame) that you might be able to get a second or third cousin. But just like y testing so much depends on who gets tested around the world. Or even at a further distance it might be able to provide some avenues of enquiry - eg a name that you might be able to cross check with student records.
It also depends if you have the disposable income right now.
Personally I'd hold out for a while and see what other people start finding and seeing what matches they get and if the matches hold genealogically.
I wouldn't be surprised if we see some false positives from this, just as it is possible to get some through y testing (convergence).
Cheers
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