These research notes are provided as-is and contain supplementary working research.
Open question
Open question: untested Y-DNA discriminator (R1b-DF19)
A direct-paternal-line Y-DNA discriminator that could test deep Gurney paternity independent of record survival is defined but untested. The FamilyTreeDNA Gurney project's Braintree Big Y-700 tester (kit 576097) sits at terminal SNP R-FTD83678 within R1b-M269 > P312 > DF19 > R-Z27053, a small continental-leaning north-west-European branch — compatible with but far too sparse and deep (pre-surname) to prove a Norman/continental deep origin. The discriminating comparison — whether a documented English-line Gurney shares the DF19 / R-Z27053 branch (the project's other R-M269 tester, kit 365744, and beyond it a recruit-and-test of a documented English line) — is unrun.
Why this conclusion
- Synthesized by Analysis Analysis: the open program reconciled to the leads catalogueThe reconciliation synthesizes the untested Y-DNA discriminator as a standing question of the open program.
- Required by Analysis Two realistic end-states for the estimate and three levers that would move itThe untested discriminating Y-DNA kit is another of the three named levers.
Sources
- FamilyTreeDNA, Gurney surname Y-DNA project (administrator Caroline Gurney) and public Discover Y-DNA haplogroup reports, familytreedna.com / discover.familytreedna.com. Consulted June 2026., FamilyTreeDNA Gurney surname project — Braintree kit 576097 (Big Y-700), terminal R-FTD83678 within R1b-M269 > P312 > DF19 > R-Z27053; public Discover haplotree, consulted June 2026
Topic file location: Research-state open questions
Technical details
- Research item:
G13-RI-000056 - Graph revision:
244 - Machine-readable JSON:
/assets/g13-graph/findings/G13-RI-000056.json
This is one research item from the John Gurney research graph; the fuller narrative treatment is in the linked topic above and the research library.