To date, multiple unrelated groups of Plunketts have been identified using their Y DNA. A plurality of Plunketts are possible Meath/Louth Plunketts and related to Saint Oliver Plunkett and the Plunketts of Dunsany and Killeen castles. To confirm this, the Plunkett Project seeks a documented member of the Plunkett British peerage to take a complimentary Y-DNA test. To apply for this test, please contact the Plunkett Surname Administrator. The Y chromosome of the other groups of Plunketts below are unrelated to each other and unrelated to the Meath/Louth Plunketts. This includes the following, all of which, are Haplotype R1b (Western European), with the exception of the G and I Haplotype groups below.

1)     PossibleMeath/Louth Plunketts of British Peerage (Dunsany & Killeen Castles as well as St. Oliver Plunkett). Can be confirmed with more certainty after testing a male who has a documented lineage to the Plunketts in the British Peerage. To confirm this, the Plunkett project seeks a documented member of the Plunkett British peerage to take a complimentary Y-DNA test. To apply for this test, please contact the Plunkett surname administrator. Members of this group are haplogroup R-M269, Z-225, Z-229 and with a terminal SNP of  R-Y16018. Members of this group should join the DF27 project.

2)     Airghialla2- Maguire of Co Fermanagh – This group consists of descendants of Donn Carrach Maguire (DCM) and are of the DCM Modal Haplotype.  Donn Carrach Maguire was the first Maguire High King of County Fermanagh and reigned from 1264 until his death in 1302. Members of this group should also join the Airghialla Mag Uidhir project for more extensive information on their lineage. For more information see http://www.familytreedna.com/public/Airghialla%20Mag%20Uidhir/.Members of this group are R-M269, L21, L513 with a terminal SNP of R-BY2598. 

3)     IrishModal Haplotype (IMH) - Members of this group are descendants of  the 5^thcentury warlord, Niall of the 9 Hostages. Trinity College scientists found an area in northwest Ireland where 21.5% of the men carry Niall’s genetic fingerprint. Members in this group should also join the Neal-O'Neal project. http://www.familytreedna.com/public/Neal-2/.For more information see also https://my.familytreedna.com/match-niall.aspx?ekit=VmbA%2bV0aEfA%3d.Because this Haplotype is so distinctive, ftDNA automatically assigns it. If you are of this Haplotype, you will have an indication on your ftDNA homepage next to your Haplotype that states “Niall of the 9 Hostages.” Members of this groupare of the R-M269, R-A260 Haplotype.

4)     Western Atlantic Modal Haplotype (WAMH) – This is the most common Y-DNAsignature of Europe’s most common Haplogroup, R-M269, constituting approximately 2.62% in Western European males. Because this Haplotype is so distinctive, ftDNA automatically assigns it. If you are of this Haplotype, you will have an indication on your ftDNA homepage next to your Haplotype that states “WAMH Western Atlantic Modal Haplotype.” For more information see https://my.familytreedna.com/match-wamh.aspx?ekit=i8EqExsUxjk%3d.

5)     Haplotype G – In Ireland, this is the ancient and rare Haplotype of Neolithic farmers. Those with this Haplotype should also join the Haplogroup G (Y-DNA) Project. For more information see http://www.familytreedna.com/public/G-YDNA/.

6)     ClanColla - Conquered Ulster in the 4th century. Members of this group should also join the Clan Colla 425 Null Project. For more information see http://www.familytreedna.com/public/clancolla425null/.Members of this group are all of the R-M269 Haplotype with a null (zero) at DYS425.

7)  McBee– Scottish – Members of this group should also join the McBee DNA Surname Project. For more information see http://www.familytreedna.com/public/McBee/.Members of this group are Haplotype R-M269, R-A663.

8) I-M223 - Probable Viking.

9) Wm Cunningham/Conyngham Plunket - Listed in Burk's Peerage, but not listed in Burk's as part of the Meath/Louth Plunkett's. This unique Western European DNA does not match the DNA of any other Plunkett's tested and is not closely allied to any particular surname.