The response from Dr Ken Nordtvedt said that my markers matched a small cluster that he later identified centred on the counties of Clare, Limerick and Tipperary in Ireland. He detailed the markers that defined the cluster and I matched. I was most surprised by this as I had expected my roots were in England. As two other Irish clusters had been identified as "North West Irish" and "South Irish", I started calling this cluster "Irish Type III" and the name has stuck.
The definitive markers Ken identified for this cluster are:-
Initially FTDNA were not testing DYS463 so the nomenclature for this marker in ySearch was that used by DNA Heritage which was 2 points lower than the NIST/ISFG standard. As of 01 March 2010, the value of this marker in Ysearch has been brought into line with the NIST/ISGF standards. If you have been tested at FTDNA, Ancestry or Genebase, enter this marker value as reported by your lab.
As no one else had taken an interest in researching this cluster, I started to gather examples from Ysearch, Sorenson (SMGF), Ancestry and various Surname Projects. In December 2006 I started these webpages to share the data I had collected. We now have over 1,100 members in the cluster.
Common Surnames are O'Brien/Brien/Bryan/Bryant, Butler, Casey, Crow(e), O'Donoghue, Hart, Hogan, Kennedy, McCraw/McGraw/McGrath, McNamara. Most seem to be Dalcassian clans, the descendants of Cormac Cas and Brian Boru. There is other evidence that this is the signature of Brian Boru and Kings of Thomond.
My paper, A Set of Distinctive Markers Defines a Y-STR Signature for Gaelic Dalcassian Families, will be of interest to members of the cluster and has been published in the Spring 2009 issue of Journal of Genetic Genealogy www.jogg.info A copy can be downloaded at www.jogg.info/51/files/Wright.pdf
The SNP L226 is the defining marker for this haplogroup. Testing positive for L226 is final confirmation that a haplotype is part of the Irish Type III haplogroup. This marker can be ordered from your FTDNA Home Page. Go to your Home Page / yDNA / Haplotree & SNPs / Now scroll down the chart to [L226!] in Blue about a quarter way down, and click the 'Add' button. Now click on the 'Order Selected SNPs' button to process your order.
But if you have the marker values shown above, then a better test to take is the R1b - L226 SNP pack which tests L226, several of the parallel SNPs, and most of the branching SNPs below L226, a total of over 100 SNPs. This can be ordered from your Home Page.
First go to your FTDNA home page, click on the Blue Button at the top 'Upgrade', then click on the Blue 'Buy Now' button under 'Advanced Tests'.
From the drop down, 'Test Type', select 'SNP Pack' and in the 'Marker' box type L226 and click 'FIND'
R1b-L226 SNP Pack is displayed. To the right is an 'Add' link, then click on the orange 'Order Now' button up the top under 'Cart'.
If you have the STR values in the chart above, you can safely ignore any warning that this test may not be appropriate for you.
If you order either the L226 Marker or the preferred R1b L226 SNP Pack, please also join the R-L226 project, https://www.familytreedna.com/groups/r-l226-project/about