Current Summary of Results
There has been west Cork lore suggesting that O'Hourihanes may have come from County Clare. From that lore came our original research hypothesis that west Cork Hourihanes could have been of Dal Cais (Irish Type III) origin. So far, no Y genetic evidence has turned up to prove either a County Clare geographic origin or a Dal Cais genetic origin.
The Cork Hourihanes tested to date are South Irish (Irish Type II, R1b-CTS4466). We are not aware of a significant presence of South Irish in the ancient territory of Clare, so our current working hypothesis is that these South Irish Hourihanes came from Tipperary or even Limerick, like their old genetic kin the O'Donovans.
There is some evidence that Horgan, Horrigan, Harrigan, Hourigan, Orgain etc. share a genetic relationship. Those who do fall into an Irish Sea (Leinster/Lagin people) subclade (R1b-Z255). There are some genealogical interrelationships within this group.
There are some Horans and Hanrahans who appear to share a remote relationship with each other and may fall into the R1b-L513 subclade, but our evidence is not as conclusive as it is for Horgan (above). Their interrelationships to each other are more remote than the interrelationships within the Horrigan group.
Some very early evidence shows that County Clare Hanrahans are Irish Type III (Dal Cais); different from the Tipperary and Westmeath Hanrahans (R1b-L513). Could this be evidence of the two Hanrahan septs (in literature)?
We have Hourihanes, Horans and Horrigans with no meaningful genetic matches and who fall outside the main groupings. So far, they are all haplogroup R1b.
The near-identical heraldry of Hourihane, Hanrahan, and Horgan has no bearing on the true genetic origins of these surnames. There is no genetic evidence to date showing that these surname categories are closely related to each other within a genealogical timeframe.
You may view our project reports here.
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