There is an FTDNA Cenel Eoghain Group. Eoghain, pronounced Owen means John. In this case, the Eoghain was an O'Neill king and a county in Northern Ireland bears his name. It is Tir Owen or Tyrone, which means Land of Owen.
The group, at the moment has three members named McCown or McCone and notice no "an" or "en" is required because it is still O(w)ne. The DNA of these three McCowns is not the same above 11/12 markers and in the Cenel Eoghain Group all three are listed under Ua Flaithbheartaigh which could be rendered in English as the Sept of O'Flaherty or O'Lafferty. Their power was greatly reduced in the 12th century by battles with the MacBrians and the O'Connors.
The Ua Flaithbheartaigh lived in Connaught, roughly in Donegal. I don't know that this one label can cover all McCowns, but I am glad that Donegal was included in our tour of Northern Ireland last
Jim McKown and I have signed up for the FTDNA 67-Y111 marker test introduction. This is new technology and is expected to greatly improve the accuracy of the Time to Most Recent Common Ancestor (TMRCA). Jim and I hope that it will pin point just how long ago our Most Recent Common
ancestor lived. Of course, we also hope it will also illuminate our link to the Maguire Clan and to that end, hope that many of our 67 marker matches also upgrade to that test.