Bowes and Bowe in Ireland
The DNA Project has at least three genetic lines with history in Ireland that each contain both the Bowes and Bowe surnames carried down different branches. That means that within each of these lines Bowes and Bowe are related, or "surname variants." However, a Bowe from one of these lines may not be related to a Bowes of another line, and vice versa. It depends whether those two lines are related. There are instances of lines where the family name in Ireland was Bowe but where it appeared to become Bowes upon immigration. Typically only the DNA Project can sort this out for an individual's family, since documentary evidence in Ireland is so limited.
Anglicizations of Gaelic O'Buadhaigh According to Woulfe [1]
Bogue*, Bohig*, Bowe, Bowes, Bowie, Boyes, Boyce, Buie, Bwee, O'Boey, O'Bowe, O'Bowige, O'Boyce, O'Boye, O'Bwoy (possible Boag)
Anglicizations of Gaelic O'Baothaghalach According to Woulfe [2]
Boetius, Bohill, Bowes
Anglicizations of Gaelic O'Buadhaigh According to MacLysaght [3]
Boag, Bogue, Bowe, Bowie, Boyce
Anglicizations Genetically Related in Ancient Eoghanacta Genealogies [4]
Brothers of Buadhaigh (Bogue, Bowe): Cronin/O'Cronin (Croinin), Healy (Ealathach), Cahalan (Cathalan), ? (Maolin); as well as Sullivan, O'Sullivan.
Bouse and Bowes in A Cork Family with Possible English Connections
See English Variants
Other Possible Variants
Boaz, Boes, Bowz, Buoy
The Irish Family History Foundation provides a list of variants for Bowes and Bowe in their database of parish records. These probably have more to do with how people search than with established variants within the surname.
Some of these have no doubt died out in usage. The DNA study aims, in part, to clarify the historical record about the association (or not) between these names, so we cast a wide net.
Alternative Origins for Some Possible Variants
See this page for helpful information on alternative origins of Buie, Bowie Bowey, Bouie, Boy, Buy, Bouwie, Buoy, Boye, Bui, Bhuie.
At least one family of Norwegian Boe took the Irish Bowe spelling to conform to neighbors in Wisconsin. I assume they were Irish and not English because Irish Bowe settled in the same county.
* See section called “A Cork Parish Records Expert Notes Boohig/Bogue Used as a Nickname to Sullivan” on the Irish Ancient Origins page.
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1. Woulfe, Patrick. Irish Names and Surnames, Collected and Edited with Explanatory and Historical Notes. Genealogical Pub. Co.: Baltimore. 1967.
2. Ibid.
3. MacLysaght, Edward. The Surnames of Ireland. Irish Academic Press Ltd.: Dublin. 1980, pp. 20, 23.
4. O' Keeffe, Eugene. The Book of Munster: Eoghanacht Genealogies. 1703.