Cosgrave Y-DNA Progress

My Y-DNA journey has been a very slow and iterative process, with 23andMe initially identifying my haplogroup as R1b1b2a1a2f*, which was later renamed to R-M269.  Through successive tests (Y37, Y67, and Y111) at FTDNA, my terminal haplogroup was further defined as R-L21, then R-DF21, and finally to R-FGC9749.  At that point my closest Y-DNA matches seemed to have Dutch and Belgian surnames, which left me wondering where my Cosgrave surname might have come from.  I took advantage of the Black Friday sale last year to purchase the Big-Y 700 test at FTDNA, which identified my only match as being Danny Blevins….not a Cosgrave or Cosgrove in sight.

Then along came Patrick (and Isabel) Cosgrove.  Patrick and Isabel’s earliest known ancestor is Thomas Cosgrove, born abt. 1812 in Dundonald, County Down, which is about 10 miles from my earliest known Cosgrave location – Malone, County Antrim, Ireland.   Patrick took the Big-Y 700 test also and received his results last week.  He was initially confirmed to be R-FGC9749, the same haplogroup as Danny Blevins and me.  I had 25 private (un-named) variants, of which Patrick shares 19, and he had two private variants which I did not share.  At last we seemed to be making progress.

But within a few days, the picture changed again at FTDNA.  Patrick and I have now been given our own terminal haplogroup – R-FT212122, a sub-clade of R-FGC9749, based on the 19 private variants that we share.  Assuming no reverse mutations, this represents the haplogroup of our common ancestor, born somewhere between 1400 and 1750.  I have only six private variants from this haplogroup and Patrick has two, so we certainly getting a clearer picture.

The chart below (format based on a chart used by Maurice Gleeson in the Gleeson surname project), will hopefully provide a clearer picture of how Patrick and myself relate to the higher level haplogroups, and to each other, and will allow for the addition of other close connections.

Our hope now is that more Cosgrave / Cosgrove men, with Ulster ancestry, will take the Big-Y 700 test, which hopefully will narrow down where and when our common ancestor may have lived.

2 thoughts on “Cosgrave Y-DNA Progress

Leave a Reply

Your email address will not be published. Required fields are marked *