🧬 Shields Surname Project – Y-DNA Lineage Summary

The Shields Surname Project currently includes 10 distinct Y-DNA lineages, each representing a genetically and historically unique branch of the Shields surname or its variants. These lineages are grouped based on shared STR markers, SNP confirmations, and documented ancestral origins. Below is a summary of each lineage, including defining characteristics and current research status.

Lineage 1 – Patrick Shields / O’Shiel Cluster

• Haplogroup: R-M269 > R-FTD2377 (subclade of R-M222)
• Estimated MRCA: c1046 CE (subject to refinement with additional testing)
• Key Ancestor: Patrick Shields / O’Shiel, b. c1695, Ireland
• Origins: Ireland, possibly Donegal or nearby regions
• Testing Status: 2 Big Y-700; 3 other testers
• Next Step: Additional Big Y-700 testing to identify downstream SNPs and refine the MRCA estimate. This may help align the lineage with the surname era (1600s–1700s) and clarify relationships among Shields/O’Shiel descendants.

Lineage 2 – William Shields of Antrim Cluster

• Haplogroup: R-M269 > R-BY32442 (includes subclades R-BY107582, R-FTC34592)
• Estimated MRCA: c1550 CE, supporting William Shields (b. c1600, Co. Antrim) as a likely common ancestor
• Origins: Northern Ireland, with branches in Scotland and the U.S.
• Testing Status: 6 Big Y-700; 14 other testers
• Next Step: Expand Big Y-700 testing to confirm branching within the group and refine the MRCA. This may help distinguish surname-era lines and clarify relationships among descendants of William Shields and related families.

Lineage 3 – Booker Shields Cluster

• Haplogroup: R-M269 > R-BY38889
• Estimated MRCA: c1150 CE (SNP-based); Y-111 match between descendants of Booker Shields (b. 1775) and William Shields (b. 1728) suggests surname origin by the mid-1700s
• Key Ancestor: William Shields, b. 1728, likely in the Carolinas or nearby region
• Origins: Southern U.S., with possible ancestral ties to Ireland
• Testing Status: 1 Big Y-700 (descendant of William Shields); 1 confirmed Y-111 match (descendant of Booker Shields)
• Genealogical Notes: A descendant of Booker Shields shares 11–22 cM with Group 4 descendants of William Bryant Shields (b. 1786, NC), likely son of Reuben Shields (b. c1754, NC). This suggests a possible female Shields ancestor or collateral relationship. No Y-DNA matches exist between the groups, indicating distinct paternal lines. No standout surnames in the Y-67 match pool (clusters like McDaniel, Pate, and McMahon likely reflect STR convergence or deeper haplogroup proximity) given they do not match at Y-111)
• Next Step: Upgrade the Y-DNA kit for the descendant of Booker Shields and recruit additional testers from both lines to clarify branching and confirm relationships.

Lineage 4 – Irish Shields–Dossey Cluster

• Haplogroup: R-M269 > R-FT38313 > R-BY62743
• Estimated MRCA: c1450 CE (based on current SNP data from two Big Y-700 testers)
• Origins: Ireland, with more recent immigrants to the U.S.
• Testing Status: 2 Big Y-700 testers (both R-BY62743); additional members tested at Y-67 or Y-111
• Genealogical Notes: Includes descendants of William Bryant Shields (b. 1786, NC), likely son of Reuben Shields (b. c1754, NC). Autosomal DNA connections exist with descendants of Booker Shields (Lineage 3), suggesting a possible female Shields ancestor or collateral relationship. Descendants of William Greenberry Dossey also appear to descend from this Shields ancestor based on STR results.
• Next Step: Recruit additional Big Y-700 testers within the group to confirm branching, refine the MRCA estimate, and identify potential subclades.

Lineage 6 – Shields/Sheils Cluster

• Haplogroup: R-M269 (STR-based estimate: R-FT227075; one tester confirmed R-L1336, which is upstream)
• Estimated MRCA: c1600–1700 CE (based on STR similarity; subject to refinement with SNP testing)
• Origins: Ireland for two testers; origin unknown for the third
• Testing Status: 1 Y-111; 1 Y-25; 1 Y-12; no Big Y-700 tests
• Genealogical Notes: Includes testers with the Shields and Sheils surnames. STR similarity suggests a shared paternal ancestor within the surname era, but the group remains under-tested.
• Next Step: Upgrade the Y-111 kit to Big Y-700 to confirm haplogroup placement and refine the MRCA estimate. Additional recruitment may help clarify surname variants and regional origins.

Lineage 7 – Unknown Shields Cluster

• Haplogroup: R-M269 > R-L1066 (STR-based estimate: possibly R-BY2707)
• Estimated MRCA: c1750–1850 CE (based on close STR match at Y-67; subject to refinement with SNP testing)
• Origins: Ireland for one tester; origin unknown for the other
• Testing Status: 2 Y-67 testers; no Big Y-700 tests
• Genealogical Notes: Includes testers with the Shields surname. STR profiles are highly similar, supporting a close paternal relationship within the surname era.
• Next Step: Recommend upgrading one or both kits to Big Y-700 to confirm haplogroup placement, identify shared SNPs, and refine the MRCA estimate. This may help clarify Irish regional origins and surname-era connections.