In a message dated 9/4/2011 4:46:35 P.M. Central Daylight Time, bcaulfield@gmail.com writes: In other words, the 17 marker signature and M222 seem to overlap, but the 17 marker signature the paper examined seems to be a subset of M222. Am I wrong? That's correct. Trinity tested for about 12 of the same basic markers used by FTDNA. Plus they added some markers at the time not tested for by FTDNA. But I think most if not all of these extra markers are now tested by FTDNA in their 67 marker set. So the Trinity markers are a sub-se of the M222 markers. Basically they identified what they called the IMH (Irish modal haplotype) using what amounts to the first 12 markers in the FTDNA set. The spreadsheet they used is still online if anyone would like to see what they did themselves. _http://www.gen.tcd.ie/molpopgen/resources.php_ (http://www.gen.tcd.ie/molpopgen/resources.php) There are several supplementary files listed. The main file is: _Supplementary Information.xls_ (http://www.gen.tcd.ie/molpopgen/link%20files/McEvoy%20et%20al%202006%20Hum%20Gen%20Sup_Info.xls) They also did a smaller sampling of UI Neill surnames. It appears below this one. The first file listed contains Eoghanachta and Dal Cais surnames from a different paper. John