Saturday, October 24, 2009

Thomas Krahn

I've mentioned Thomas Krahn before, here, here, here and here.    Thomas formerly had his own genetic lab in Germany, DNA Fingerprint, where he was always one of the 'good guys' offering new tests and whatever else he could to push this new science/hobby forward.

One of FTDNA's better moves was to acquire Thomas' services and he continues to do that in his role there.    An example is this recent posting by him on the DNA list:

"After some time I got tired drawing Y chromosome SNP trees with graphics programs and I also wanted to get something where I can search for haplogroup names and SNP names in a plain HTML document with the search function in my browser.

That's why two weeks ago I started to code a database driven tree software that can display and edit the Y chromosome tree and that logs all the changes to the phylogeny in a database.    To be honest I found already a basic backbone structure software at .    However there where many parts missing so I modified the code to our needs.

You can have a look at to see it working in the "alpha version".    I don't give any warranty that all data are correct yet.    However you are welcome to check it out and get the picture about the philosophy behind this project.

When you first come to the web page it will display the full YCC tree as it is printed on the posters that we distributed at the last FTDNA conference at the beginning of this year.    The nodes of the tree are entirely based on the marker names and the haplogroup names are only pulled out from a database table since they are expected to change over time.    Wherever there is a difference between the YCC and ISOGG nomenclature the ISOGG haplogroup name is displayed next to it.    You'll still see a few quirks with this but I'm working to get them cleared out.

Whenever you click on a node with the "root" symbol, this will open a new sub-tree which focuses on the branches below this new root.    The URL for this sub-tree can be bookmarked so that you can quickly focus on the part of the tree that you are interested in.    The marker names are linked to the ymap Y chromosome map.    I'm thinking about a way to get a link back from ymap to ytree as well but I can't imagine how it should work in detail right now.    I'm open for suggestions.

On the top of the page you can always switch back and forth between the YCC tree and my most current Draft tree which includes the most recent SNPs discovered from the WTY project or from elsewhere.    The nodes that have changed are marked with a little yellow star which will gray out the older the last change gets.    So the newest changes will always appear in bright yellow.    If you hover your mouse above a star you can see the days that have passed since the last change was done.    Clicking on the star will brig you to a table that lists all the changes that have been recorded for this node.

I'd be happy to hear your comments and suggestions.    Of course if you see an error please report it to me so that I can fix it.    Hopefully this Ytree will be a helpful tool and not make more confusion about nomenclature and unresolved branches.    In any case I felt that I need this tool by myself to keep track of the rapidly changing phylogenies with the new markers that are discovered recently.

I hope this helps,


It certainly does help, Thomas.    Thank you.

I plan to incorporate links to Thomas' YTree into the Berry Family DNA Project website wherever it seems appropriate, certainly in the pages of those folks who have done advanced SNP testing.


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