Wednesday 18 July 2012

Gedmatch is great!

I really can't praise the work of the volunteers at Gedmatch enough, they do a superb job. If you have done a DNA test via 23andme or FamilytreeDNA Family Finder and you are interested in finding more clues about your ancestry do upload your data to Gedmatch. It is anonymous and you are identified via an ID number and your emal should you wish to submit it (this allows potential cousins at Gedmatch to contact you).

Once you have uploaded your data to Gedmatch it is safely stored and you merely enter your ID number whenever you wish to check anything, so no messy uploading of your raw data files everytime!

They have recently added some "admixture calculators" which you can run your data through. These predict how much of your DNA comes from certain regions of the world. It's all based on statistics and I don't know how they do it, but it's interesting! It is through these calculators that I have been able to see that my mother has some Eastern European ancestry based on her higher scores compared to people who are 100% British. And really to use these calculators and make any sense of them, you need to compare your scores to people of a similar ethnic origin to you, right down to similar regions of a country if you can.
You can easily compare your results by posting them on the forums at 23andme and FTDNA-search for Gedmatch in each and you will find a multitude of threads about it!

One handy thing about Gedmatch is it allows you to reduce the "safe" threshold of 7cM (Centimorgans, a unit of measurement of DNA) and 700 SNPs (the little bits that make up segments of DNA).
23andme and FTDNA use thresholds around this number to make sure that the matches you get to other people are real and not just "noise." But many people have been successful at finding connections to people below this safety net cut off. It must be used with caution though. It has been suggested by some that anything between 5cM and 7cM has a 50/50 chance of being from a shared ancestor within a genealogical timeframe. It is possible that segment this small could be ancient throwbacks representative of an ethnic group rather than a specific family from the ethnic group. It could also be the computer that works it all out having a bit of a moment and joining to little fragments of DNA together (eg a tiny bit from your Mum and a tiny bit from your Dad) to make a bigger one which it thinks is worthy of a mention. 23andme and FTDNA do allow you to experiment below the 7cM threshold (see Ancestry Finder at 23andme or play around with the chromosome browser at FTDNA) and 23andme advise anything near to 5cM be taken with a pinch of salt.

So why would you want to use Gedmatch to go below this threshold? Perhaps I am missing out, but I do ignore anything below 6cM, however I decided to compare my mother's 5th cousin of Szekely descent and this cousins Granddaughter using 3cM! Shock horror, I don't know what came over me, I blame my recent root canal.

Sure enough they shared little segments with my Mum, some were the same others different. So I focussed on the segments that they shared in common with each other and my Mum (this would infer that the Grandmother had passed them to the Granddaughter). One segment in particular was on chromosome 18 both roughly 3.7cM and 648 SNPs.
I had been intrigued by a mystery Gedmatch user that was clearly related to both of them, so I decided to compare them to my mother too. Sure enough, they matched in this location too. I emailled the person in chrage of looking after the family Gedmatch accounts and it turns out the mystery match is the Grandmother's son!
So there is a small segment that has been passed from mother to son to daughter that is also shared by my mother via a shared ancestor in the past! Or at least that is how it appears, I have to take it with a pinch of salt but it seems plausible to me!

Gedmatch also ran a rare SNP feature which has since been removed and will have it's own website, which allows you to see what rare SNPs you have which may suggest a connection to a region.
Whilst it was still available I was able to compare my mother to the Grandmother and the Granddaughter to see if they all shared any rare SNPs. They did, one. Origin of the SNP was listed as Spain, Poland or Hungary! As they both have Hungarian ancestry I was quite impressed! It doesn't prove any recent connections using this method, but it was nice to have it supported by people we knew had ancestry from Hungary.

So if you have data, get uploading! If you find new cousins or find something out about your ancestry via Gedmatch, please consider making a donation to support their hard work!
http://www.gedmatch.com/

Friday 11 May 2012

Gedmatch matches to Eastern Europe

Just a quick tally of Gedmatch matches over 700 cM and 700 SNPs:
7.1cM Ukraine
7.4cM Hungary
7.4cM Russia (Samara/Kazan region)
7.7cM Russia
8.4cM Hungary/Romania (Szekely cousin)
9.2cM Lithuania/Latvia (5th cousin)
9.5cM Lithuania
Addition using FTDNA kit:
7.3cM Hungary/Romania (Szekely cousin Granddaughter)

Tuesday 1 May 2012

Latest Gedmatch Eurogenes chromosome comparison results.

I compared the K12 and the Hunter-Gatherer vs Farmer calculators with the Szekely cousin who has shown "peaks" in common in my previous post.
This time there is still something in that location that is shared in common but it appears a lot smaller. Not sure about the Pygmy gatherer, but African was picked up on one of the other comparisons too. Volga-Ural makes more sense.


Hungarian match number 6!

Yes via Gedmatch, we now have Hungarian match number 6. They don't think they have any Szekely ancestry, but I don't see why we can't have regular Hungarian ancestry too!
All their matches are either Jewish or Eastern European, there aren't any UK matches. I say this because it is always nice to affirm as much as possible the fact that the match is not possibly on our UK side!

Monday 26 March 2012

Gedmatch Eurogenes k12b by chr comparison


Below: Dodecad by chr admixture comparison.


Below: Eurogenes k12b by chr admixture comparison.

Gedmatch have released various admixture tools from the Eurogenes project. One of them allows you to compare relatives at Gedmatch on the chromosome segments you share with them and will break your matches down into admixture proportions.

I compared my mother and one of her Szekely cousins using this feature and attached is the result. I also compared the segment using the Dodecad utility which does a similar thing.
Once again there is a visible "peak" which Dr Ann Turner tells me supports the fact that the match is real-the size of the peaks do not necessarily have to be the same as siblings etc would inherit varying amounts of the same DNA. What is really exciting is what the peak represents-Dodecad suggests Paleo-African which I'm not sure about, but Eurogenes suggests North Asian, which I would think is more plausible or at least something to do with the Szekely.

Sunday 29 January 2012

Finally a location and some names!

Exciting news for me the other day. I got in touch with one of my mother's 5th cousins (let's call them Cousin A) who is of Hungarian descent as I noticed that she matches another member of this cousin's family over at Gedmatch. And it's a good job I did get in touch, because they told me that since I had last wrote, they had been in touch with Mum's other 5th cousin of Hungarian descent (cousin B) of which me, my mother and cousin A are also related to (that is we are all descended from the same ancestor).

Cousin A and cousin B had managed to locate a city, timeframe and 3 surnames that they both shared in common! I didn't realise, but their Hungarian ancestry is in fact Szekley. The city they have both been able to find a connection to is Gyergyoszentmiklos, in Szekely Land, Romania. The surnames in common date back 8 generations making their common ancestors their GGGGGreat Grandparents approximately (my mother, cousin A and cousin B being of similar age). So they are in theory, 6th cousins. The 23andme prediction was 5th to distant cousins.

Cousin A tells me that the Szekely were a close community and that marriages within the community were common, so it is possible that these surnames they have found were all related to each other and it is impossible at this time to narrow the link down further.

On reading up about the Szekely, it seems that some moved to Bucovina in the second half of the 18th Century. Perhaps this included my ancestors-descendants who branched off from our common ancestors. This group seem to be the ones who later emmigrated to the USA in the late 19th Century, so it would make sense, or perhaps they married into a Hungarian family or a German family which later went on the the US.

What is interesting is that Bukovina is not far from the Galicia region, where my mother has other matches.

Really chuffed, it may be a distant connection, but it has made the connection solid!