Sunday, November 16, 2025

Major Update to the Cathcart Y-DNA Project — New Groupings and Research Findings

Over the past several months, I have been updating and reorganizing the subgroup structure for the Cathcart Surname Y-DNA Project. With the addition of several new testers, upgraded results, autosomal matches, and stronger genealogical evidence, we now have a much clearer picture of the major Cathcart paternal-line branches.

This has allowed us to refine existing groups and create several new ones, better reflecting the true genetic landscape of the extended Cathcart family. The goal is always the same:
to help project members understand where their paternal line fits into the broader Cathcart story.

Below is a summary of the most significant updates.


1. Expanded Group 1: The Ulster / Lowland Scotland Cathcart Line

Group 1—our largest and oldest Cathcart lineage—has been reorganized into a set of well-defined subgroups based on Y-DNA clustering, genealogical records, and known migration paths. These now include:

  • 1A: James Cathcart of York/Fairfield County, South Carolina

  • 1B: Joseph (“the Spy”) Cathcart and his South Carolina → Tennessee descendants

  • 1C: Samuel Cathcart of Spartanburg County, South Carolina

  • 1D: William & Mary Cathcart of York County, SC (Lanarkshire/Antrim origins)

  • 1E: John & Mary/Felicity of Mecklenburg Co., NC → Coweta Co., GA

  • 1F: John Kithcart of County Antrim → Fayette County, Pennsylvania

  • 1G: John & Martha McDowell Cathcart of Kells/Connor Parish → Victoria, Australia

  • 1H: William (and possibly Alexander) Cathcart of County Fermanagh, Ireland

  • 1I: North Carolina → Tennessee Cathcart line (Robert Allen Cathcart, b. 1796 NC)

These additions reflect strong Y-DNA patterns within R-M269 and align well with known migration routes from Ulster and Lowland Scotland into the United States.


2. New Structure for Haplogroup I Cathcart Lines (Group 4)

What was previously a single group has now been separated to reflect two unrelated paternal lineages:

  • 4A — I-FTD52851 Scottish Cathcart Line:
    A well-supported Y-DNA cluster shared by descendants of William Wallace Cathcart, James Allen Cathcart, and David Blair Cathcart.

  • 4B — I-M253 Independent Line:
    A separate paternal lineage whose closest matches carry the Lady surname. This subgroup will remain independent until additional Cathcart testers with similar profiles appear.


3. New Group 5 — Independent E-Haplogroup Cathcart Line

A new subgroup has been created for a tester whose paternal haplogroup (E-M4901) is not related to the R- or I-haplogroup Cathcart lines. His earliest known ancestor is Leroy Earl Cathcart. This represents an independent Cathcart paternal origin that developed within the United States.


4. Updated Placement of Autosomal-Only Testers

Several project members have taken the Family Finder (autosomal) test but not Y-DNA. Where appropriate, these members have been placed provisionally within the subgroup that best fits their:

  • known genealogy,

  • family records, and

  • autosomal matches to confirmed Y-DNA testers.

These placements remain tentative until a male-line descendant can take a Y-DNA test to confirm the position.


5. Improved Use of Autosomal Triangulation

In cases where Y-DNA does not exist or where the genealogy is uncertain, autosomal DNA has been used to identify clusters of relatives who descend from the same ancestral branch.
For example:

  • Matches among descendants of the Joseph (“the Spy”) Cathcart line

  • Confirmed Tennessee-line (Monroe County) descendants

  • Multi-person triangulations supporting connections among otherwise unlinked branches

These autosomal findings have helped refine subgroup placement and suggest avenues for future research.


6. Still a Work in Progress

Although the revised structure is much clearer than before, the project is still a work in progress. As new members join, and as more testers upgrade to Y-67, Y-111, or Big Y-700, the groupings will continue to strengthen and evolve.

I welcome:

  • suggestions,

  • corrections,

  • new documentation,

  • feedback from descendants, and

  • additional historical material

from anyone researching the Cathcart surname in Ireland, Scotland, or the United States.


7. Thank You

Thank you to everyone who has contributed Y-DNA results, autosomal connections, genealogical research, and historical records. Your participation makes this project meaningful and helps all of us understand our shared heritage more clearly.

If you have questions about your placement or wish to provide updated family information, please feel free to contact me.

— John Cathcart
Project Administrator, Cathcart Surname DNA Project