DNA Evidence Analysis
Page Update — Chromosome 2 Segment Triangulation
This page was originally published in December 2025. Since then, segment-level DNA evidence and a reconstructed paternal kit methodology have established the Donaghmoyne genetic network at confirmed evidence level. The evidence tiers and connection-status assessments below have been updated accordingly, but the family-line cluster matrices remain as documented in the original analysis. For the segment-level evidence base — including reconstructed-kit methodology, mathematical triangulation results, and confirmed paternal segment data for 13+ cluster matches — see the Chromosome 2 Triangulation Analysis component page.
DNA testing has become a powerful tool for genealogical research, but interpreting genetic evidence requires careful attention to match levels, testing limitations, and the distinction between correlation and proof. This analysis examines the DNA evidence connecting four families who married in Donaghmoyne parish between 1841 and 1858. The analysis is organized in tiers reflecting the strength of evidence supporting each connection, ranging from documented segment-level confirmation to threshold matches at the edge of significance.
The evidence varies significantly across the network. Some connections are supported by strong internal matches that confirm documented relationships. Others rest on cross-network matches at threshold levels that suggest but do not prove biological connections. This page presents what we know, what we suspect, and where the evidence remains inconclusive.
Understanding DNA Match Levels and Evidence Tiers
Strong matches (100+ cM): Reliably indicate a biological relationship, typically within 4–5 generations. These matches are almost certainly "identical by descent" (IBD)—inherited from a common ancestor.
Moderate matches (30–99 cM): Likely indicate a relationship, but the common ancestor may be 5–7 generations back. Most matches in this range are IBD, though some smaller segments may be coincidental.
Threshold matches (15–29 cM): Require careful interpretation. While they can represent distant cousin relationships, matches in this range can also occur by chance between unrelated individuals, especially when only one segment is shared.
Weak matches (8–14 cM): At the edge of significance. These matches frequently occur by chance ("identical by chance" or IBC) and should not be considered evidence of relationship without corroborating factors such as shared matches, geographic clustering, or documentary evidence.
Triangulated segments and reconstructed-kit confirmation: Above the cM-level framework, two additional tools strengthen evidence reliability. Triangulated segments — confirmed when three or more matches share the same DNA region with each other and with the kit owner — establish common ancestral inheritance regardless of individual cM level. Reconstructed-kit one-to-one comparison — testing a match directly against a deceased ancestor's reconstructed paternal or maternal genome — establishes which parental line the shared segment came through. Both tools are applied in this case study and detailed in the Chromosome 2 Triangulation Analysis.
The Four DNA Clusters
Current testing status and internal match strength for each family line
Chicago Cluster
Testing Status
4 testers descend from Mary Ann Hamall Byron (Owen's sister). Three testers are a father and his two daughters—effectively two independent data points. 5 testers descend from Owen Hamall's direct line, but all are siblings (children of Thomas Kenny Hamall), functioning as a single data point in conventional autosomal analysis. No 1st, 2nd, or 3rd paternal-side cousins exist for triangulation.
The Bottleneck Resolution
The bottleneck has now been substantially addressed through reconstructed paternal kit methodology. Four sibling kits plus the maternal kit were used to reconstruct Thomas Kenny Hamall's paternal genome (uploaded to GEDmatch as a research kit). The reconstruction was validated across five children including independent platform validation via a fifth sibling tested at Ancestry. The reconstructed kit now functions as a stable paternal comparator, enabling direct paternal-inheritance confirmation for any candidate cluster match. See methodology details.
Cross-Network Matches
The chromosome 2 segment evidence demonstrates that the Chicago line does share confirmed paternal segments with multiple Donaghmoyne network families on chromosome 2 — including descendants of the Hamill of Dian (T.S.), McGeough (S.M., M.R.), Gartlan (J.L. and family), Trainor (B.R.), and McCabe (J.S.) lines. These connections were not detectable through conventional one-to-many search but became visible once the reconstructed kit was available. The McMahon-cluster question remains a separate research thread.
| Testers | 9 (4 + 5 siblings) |
| Independent lines | 2 (Mary Ann Byron + Thomas Kenny direct) |
| Internal matches | 15–20 cM range |
| Cross-network (Chr 2) | 13+ confirmed paternal segments |
| Reconstructed paternal kit | Yes (validated) |
Wisconsin Cluster
Testing Status
Multiple testers across several children's lines. Strong internal matches confirm common descent from Owen and Ann. Descendants spread from Wisconsin to Nebraska.
Internal Evidence
Internal matches of 52–74 cM between descendants of different children confirm the documented family structure. This cluster has the most robust internal validation after the James/Ann Gartlan line.
Cross-Network Matches
Matches to Chicago line: 21–34 cM (23andMe), 10–17 cM (Ancestry). These levels are suggestive of a relationship but not conclusive. The brother hypothesis (Owen and Henry as siblings) remains unproven.
| Testers | 8+ |
| Children's lines represented | 3–4 |
| Internal matches | 52–74 cM |
| Cross-network (Chicago) | 10–34 cM |
Joliet Cluster
Testing Status
9 testers across 3 children's lines (Mary Ann McCanna Kelly, Nellie McCanna Sheridan, Frank McCanna). Strong internal matches confirm the documented sibling relationships.
Internal Evidence
Internal matches of 27–67 cM between descendants of different children validate the family structure. The McCanna family is well-documented in Joliet records.
Cross-Network Matches
Matches to Chicago line: 8–15 cM—at threshold of significance. New discovery: D.G. (Catherine Hammill Linstead descendant) shows 28–32 cM to Nellie McCanna descendants, a more significant connection requiring further investigation.
| Testers | 9 |
| Children's lines represented | 3 |
| Internal matches | 27–67 cM |
| Cross-network (Chicago) | 8–15 cM |
Montana/Missouri Cluster
Testing Status
14 testers across 5 children's lines: James (Montana), Patrick (Missouri), Henry (Missouri), Anna (Ireland), Bridget (Ireland). The most comprehensively tested cluster with the strongest internal evidence.
Internal Evidence
PROVEN: Documentary evidence (including Peter Hamill's 1949 death certificate naming both parents) combined with strong DNA matches (23–228 cM between children's lines, 1627–3463 cM between close relatives) definitively establishes the sibling relationships.
Cross-Network Matches
Connection to Chicago line is indirect—one promising match identified on another platform. Shared matches through other clusters point to common Monaghan ancestry. The exact relationship remains under investigation.
| Testers | 14 |
| Children's lines represented | 5 |
| Internal matches | 23–228 cM |
| Cross-network (Chicago) | Indirect only |
DNA Match Matrices
Visual evidence of shared DNA across the network
The following matrices show shared centimorgans (cM) between tested descendants. Names have been anonymized to protect privacy. The ancestor from whom each tester descends is noted in parentheses. Higher cM values indicate closer relationships—color intensity reflects match strength.
Chicago ↔ Wisconsin: 23andMe Evidence
M.H.M. (Chicago) matches descendants of three different children of Owen Hammel & Ann King
KEY FINDING — 23ANDME
M.H.M. (Chicago line) shares 21–34 cM with descendants of three different children of Owen Hammel & Ann King (Wisconsin): Anna Hammel Engel, Mary E Hammel Bucklin, and Henry Patrick Hammel.
This pattern—matching multiple descendants across different branches of the same family—is consistent with what we would expect if Owen Hammel (Wisconsin) and Henry Hamall (Chicago) were brothers. The match levels of 21–34 cM are consistent with 3rd cousins once removed to 4th cousins, the expected relationship if the common ancestors were brothers. However, matches at these levels can also occur by chance, so this evidence is suggestive rather than conclusive.
Chicago ↔ Wisconsin: Ancestry Confirmation
Cross-platform verification of the Chicago-Wisconsin connection
KEY FINDING — ANCESTRY
On Ancestry, M.H.M. (Chicago) matches Wisconsin Hammel descendants at 10–17 cM—lower than 23andMe but still consistent across multiple testers from different branches. The consistency of matches across both platforms strengthens the hypothesis.
The high matches within the Wisconsin line (such as 206 cM between M.G. and S.R., both descended from Mary E Hammel Bucklin) confirm that testers correctly descend from the documented ancestors. The cross-network matches to Chicago, while lower, appear across multiple independent lines.
Owen Hammel & Ann King: 23andMe Internal Matches
Strong internal matches confirm documented family structure
| Tester (Ancestor) | M.H.M.Chicago | R.V.E.Anna Engel | L.L.Mary Bucklin | L.F.Henry Patrick | C.F.Gartlan* |
|---|---|---|---|---|---|
| M.H.M.Henry Hamall & Mary McMahon (Chicago) | — | 34 | 33 | 21 | 23 |
| R.V.E.Anna Hammel Engel (Wisconsin) | 34 | — | 74 | 26 | 16 |
| L.L.Mary E Hammel Bucklin (Wisconsin) | 33 | 74 | — | 52 | 16 |
| L.F.Henry Patrick Hammel (Wisconsin) | 21 | 26 | 52 | — | 0 |
| C.F.James Hamill & Ann Gartlan (Donaghmoyne)* | 23 | 16 | 16 | 0 | — |
Key Finding — Wisconsin Line Validation
Internal matches between Wisconsin descendants (52–74 cM between children of different Owen/Ann children) confirm the documented family structure. These match levels are exactly what we would expect for the generational distance involved.
The inclusion of C.F. (James Hamill & Ann Gartlan descendant) shows matches of 16–23 cM to Chicago and Wisconsin testers—suggesting a more distant connection to the Donaghmoyne network, though at threshold levels requiring careful interpretation.
Owen Hammel & Ann King: Full Network View (Ancestry)
Comprehensive matrix including Wisconsin, Chicago, and McCanna descendants
| Tester (Ancestor) | M.H.M.Chicago | T.L.Anna Engel | C.L.Henry Patrick | M.G.Mary Bucklin | S.R.Mary Bucklin | T.L.2Henry Patrick | J.C.Mary Bucklin | J.Y.Mary Bucklin | M.S.McCanna* | B.W.Mary Bucklin | C.L.2Mary Bucklin | K.B.McCanna* | H.C.McCanna* | J.R.McCanna* |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M.H.M.Henry Hamall & Mary McMahon (Chicago) | — | 14 | 17 | 17 | 10 | 15 | 14 | 15 | 13 | 13 | 10 | 11 | 8 | 15 |
| T.L.Anna Hammel Engel (Wisconsin) | 14 | — | 35 | 55 | 33 | 23 | 24 | 22 | 0 | 0 | 0 | 0 | 0 | 0 |
| C.L.Henry Patrick Hammel (Wisconsin) | 17 | 35 | — | 0 | 46 | 3477 | 0 | 0 | 0 | 0 | 0 | 27 | 25 | 0 |
| M.G.Mary E Hammel Bucklin (Wisconsin) | 17 | 55 | 0 | — | 206 | 0 | 1604 | 3476 | 35 | 1889 | 293 | 0 | 0 | 0 |
| S.R.Mary E Hammel Bucklin (Wisconsin) | 10 | 33 | 46 | 206 | — | 0 | 38 | 52 | 49 | 131 | 2785 | 47 | 0 | 0 |
| T.L.2Henry Patrick Hammel (Wisconsin) | 15 | 23 | 3477 | 0 | 0 | — | 0 | 0 | 0 | 0 | 0 | 0 | 26 | 0 |
| J.C.Mary E Hammel Bucklin (Wisconsin) | 14 | 24 | 0 | 1604 | 38 | 0 | — | 810 | 0 | 520 | 167 | 0 | 0 | 0 |
| J.Y.Mary E Hammel Bucklin (Wisconsin) | 15 | 22 | 0 | 3476 | 52 | 0 | 810 | — | 0 | 1764 | 133 | 0 | 0 | 0 |
| M.S.Susan Hamill & Charles McCanna* | 13 | 0 | 0 | 35 | 49 | 0 | 0 | 0 | — | 22 | 60 | 283 | 140 | 369 |
| B.W.Mary E Hammel Bucklin (Wisconsin) | 13 | 0 | 0 | 1889 | 131 | 0 | 520 | 1764 | 22 | — | 163 | 0 | 0 | 0 |
| C.L.2Mary E Hammel Bucklin (Wisconsin) | 10 | 0 | 0 | 293 | 2785 | 0 | 167 | 133 | 60 | 163 | — | 0 | 0 | 0 |
| K.B.Susan Hamill & Charles McCanna* | 11 | 0 | 27 | 0 | 47 | 0 | 0 | 0 | 283 | 0 | 0 | — | 143 | 317 |
| H.C.Susan Hamill & Charles McCanna* | 8 | 0 | 25 | 0 | 0 | 26 | 0 | 0 | 140 | 0 | 0 | 143 | — | 114 |
| J.R.Susan Hamill & Charles McCanna* | 15 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 369 | 0 | 0 | 317 | 114 | — |
Key Finding — Cross-Network Patterns
This comprehensive matrix reveals the complexity of the network. Strong internal matches within the Wisconsin line (1604–3477 cM for close relatives, 131–293 cM for more distant cousins) confirm documented relationships.
Cross-network patterns are more varied: Chicago (M.H.M.) shows consistent 8–17 cM matches to Wisconsin testers, while McCanna descendants (M.S., K.B., H.C., J.R.) show sporadic matches. The pattern suggests possible relationships but at levels requiring segment analysis for confirmation.
Susan Hamill & Charles McCanna: Verified Matches
Internal McCanna matches plus cross-network connections to Chicago
| Tester (Ancestor) | M.H.M.Chicago | C.H.M.Chicago | M.S.Nellie | J.G.Susan | S.M.Mary Anna | S.T.Mary Anna | L.M.Mary Anna | S.E.Nellie | J.R.Nellie | K.B.Nellie | H.C.Frank |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M.H.M.Henry Hamall & Mary McMahon (Chicago) | — | 2767 | 13 | 8 | 10 | 8 | 8 | 15 | 15 | 11 | 8 |
| C.H.M.Henry Hamall & Mary McMahon (Chicago) | 2767 | — | 23 | 14 | 11 | 0 | 0 | 17 | 17 | 11 | 12 |
| M.S.Ellen B "Nellie" McCanna Sheridan | 13 | 23 | — | 3440 | 67 | 51 | 50 | 253 | 369 | 283 | 140 |
| J.G.Susan Hamill & Charles McCanna | 8 | 14 | 3440 | — | 40 | 37 | 33 | 139 | 205 | 140 | 41 |
| S.M.Mary Anna McCanna Kelly | 10 | 11 | 67 | 40 | — | 2700 | 1864 | 36 | 27 | 0 | 37 |
| S.T.Mary Anna McCanna Kelly | 8 | 0 | 51 | 37 | 2700 | — | 3458 | 49 | 47 | 0 | 0 |
| L.M.Mary Anna McCanna Kelly | 8 | 0 | 50 | 33 | 1864 | 3458 | — | 0 | 37 | 0 | 0 |
| S.E.Ellen B "Nellie" McCanna Sheridan | 15 | 17 | 253 | 139 | 36 | 49 | 0 | — | 3486 | 15 | 37 |
| J.R.Ellen B "Nellie" McCanna Sheridan | 15 | 17 | 369 | 205 | 27 | 47 | 37 | 3486 | — | 317 | 114 |
| K.B.Ellen B "Nellie" McCanna Sheridan | 11 | 11 | 283 | 140 | 0 | 0 | 0 | 15 | 317 | — | 143 |
| H.C.Frank Charles McCanna | 8 | 12 | 140 | 41 | 37 | 0 | 0 | 37 | 114 | 143 | — |
Key Finding — McCanna Network
Strong internal matches within the McCanna family (1864–3486 cM for close relatives, 27–369 cM for documented cousins across different children's lines) confirm the family structure. Three children's lines are represented: Mary Anna McCanna Kelly, Ellen B "Nellie" McCanna Sheridan, and Frank Charles McCanna.
Cross-network matches to Chicago (8–23 cM) are at threshold levels. The pattern suggests Susan Hamill may have been related to Henry Hamall, but the match levels are too low for confident conclusions without segment triangulation.
Cross-Network Match Analysis
What connects these four families—and what doesn't
The central question of this research is whether the four couples who married in Donaghmoyne parish were biologically related. The cross-network DNA evidence is now organized at five evidence tiers reflecting the strength of supporting documentation for each connection. The CONFIRMED tier — added since the December 2025 publication — captures findings now backed by chromosome 2 segment triangulation across multiple platforms plus reconstructed-kit paternal verification. The other tiers preserve the original framework with updated assessments based on the new segment evidence.
| Connection | Evidence Base | Tier | Interpretation |
|---|---|---|---|
| Donaghmoyne Genetic Network (cluster level) | Chr 2 triangulation + reconstructed kit + multi-platform | CONFIRMED | 13+ confirmed paternal matches across 17 surname clusters |
| James/Gartlan Internal Sibling Group | 23–228 cM + 1949 death certificate | PROVEN | Sibling relationship documented via DNA + primary source |
| Owen/King Family Internal Structure | 52–74 cM internal | PROVEN | Common descent from Owen & Ann confirmed |
| McCanna Family Internal Structure | 27–67 cM internal | PROVEN | Common descent from Charles & Susan confirmed |
| Henry Hamall ↔ Owen Hammel | 10–34 cM + Chr 2 segment evidence | SUGGESTIVE | Cluster evidence corroborates; brother-vs-cousin question requires documentary work |
| Henry Hamall ↔ James Hamill of Dian | Chr 2 segment + 1881 census evidence | SUGGESTIVE | Tara Smith confirmed paternal; Andrew Hamill (1793–1866) right generation; specific MRCA pending |
| Henry Hamall ↔ Susan Hamill McCanna | 8–15 cM | EXPLORING | At threshold; segment-level analysis specific to this pairing pending |
| Wisconsin ↔ Joliet | Sporadic | EXPLORING | Some matches identified; pattern not yet sufficiently dense for hypothesis |
| Chicago ↔ McMahon Cluster | 15–20 cM + Louth McMahon ancestor in cluster trees | EXPLORING | Ann Matthews Clarke tree shows John McMahon Louth (1764–); supports Mary McMahon hypothesis |
The McMahon Question — Updated Status
The December 2025 analysis flagged a McMahon cluster finding as a possible complication for the brother hypothesis. Subsequent research has clarified the McMahon thread rather than complicated it. A confirmed paternal cluster match (Ann Matthews Clarke) carries documented McMahon ancestry traced to John McMahon Louth (1764–), with three further generations documented back to John McMahon (1702–1789). The "Louth" attribution is significant: Mary McMahon, Owen Hamall's mother (died 1874 Montreal), is documented in the existing case study but her origin remains uncertain. The McMahon families documented in Ann Matthews Clarke's tree — Louth-rooted, of the right generation to be ancestral to Mary McMahon — represent a tractable documentary research lead rather than a contradicting hypothesis. Both the Hamill sibling hypothesis and the McMahon-line connection are now active research threads with documentary anchor points.
Key Findings & Limitations
What the DNA evidence tells us—and what it doesn't
James/Ann Gartlan Siblings: PROVEN
The sibling relationship between James (Montana), Patrick (Missouri), Henry (Missouri), Anna (Ireland), and Bridget (Ireland) is proven through documentary evidence and validated by strong DNA matches (23–228 cM). This is the anchor point of the network at the family-line level.
Internal Clusters: VALIDATED
Each of the four clusters shows internal DNA matches that confirm the documented family structures. Descendants of the same couple share DNA at expected levels for their generational distance.
Brother Hypothesis: SUGGESTIVE
The hypothesis that Henry Hamall and Owen Hammel were brothers is supported by chromosome 2 segment evidence linking their descendant lines through the broader Donaghmoyne network, plus the documentary parish-marriage record (Donaghmoyne 1841 and 1846), plus naming patterns. The brother-versus-cousin question — whether they shared parents or grandparents — remains a documentary research question.
Donaghmoyne Genetic Network: CONFIRMED
The endogamous Donaghmoyne genetic network is confirmed at cluster level through chromosome 2 segment triangulation (9 MyHeritage matches mathematically triangulating + 13+ paternal matches confirmed via reconstructed kit) and a 17-surname signature concentrated in southeast County Monaghan and adjacent Louth. Specific MRCA-level relationships within the network remain documentary research questions.
McMahon-Louth Connection: ACTIVE LEAD
A confirmed paternal cluster match documents McMahon ancestry traced to John McMahon Louth (1764–). The dates and geography align with potential ancestral ties to Mary McMahon (Owen Hamall's mother, died Montreal 1874). This provides a tractable documentary research lead in Louth Catholic parish records 1790s–1810s.
Chicago Bottleneck: RESOLVED
The Chicago paternal-line bottleneck has been substantially addressed through reconstructed paternal kit methodology. Four sibling kits plus the maternal kit produced a validated reconstruction of Thomas Kenny Hamall's paternal genome, providing a stable comparator for any future paternal candidate match. Y-DNA testing remains a complementary path for surname-specific confirmation but is no longer the only available method for paternal-line analysis.
Research Priorities Going Forward
- Pre-Famine Documentary Research: The primary research gap is now documentary rather than genetic. Catholic Qualification Rolls 1778–1790, Tithe Applotment Books 1823–1838, and surviving estate records for County Monaghan are required to identify the specific ancestral couple connecting the four documented Donaghmoyne couples.
- Donaghmoyne Catholic Parish Records 1834–1860: Hamill, Gartlan, McEneaney, and McGeough family reconstruction in the parish where these families were documented; specifically targeting Andrew Hamill (1793–1866) and his relationship to Henry Hamall.
- 1841 England Census: Locate Andrew Hamill (1793–1866) and the James Anthony Hamill family to establish emigration timing and identify Liverpool-based Hamill household connections.
- Louth Catholic Records: McMahon families 1790s–1810s, particularly testing the documented John McMahon Louth (1764–) ancestry against the Mary McMahon → Owen Hamall hypothesis.
- Continued Reconstructed Kit Comparisons: Systematic one-to-one comparison of new paternal candidate matches against the reconstructed kit as cluster matches are identified or transferred to GEDmatch.
- Y-DNA Testing as Complementary Path: Big Y-700 tests from male-line Hamill/Hamall/Hammel descendants would provide deeper paternal-line resolution beyond autosomal DNA's effective range. No longer the primary methodology, but valuable surname-specific confirmation.
- Catherine Hammill Linstead Connection: The D.G. match (28–32 cM to McCanna descendants) warrants continued investigation as a potentially significant cross-network link; pending raw DNA upload to a chromosome-browser platform.
Summary Assessment
The DNA evidence now demonstrates the existence of the Donaghmoyne genetic network at confirmed cluster level, with the subject's paternal Hamall line documented as descending from this network through chromosome 2 segment triangulation and reconstructed paternal kit verification. The James Hamill & Ann Gartlan sibling group remains independently documented through both DNA and primary documentary evidence. The Chicago paternal-line bottleneck that previously limited analysis has been substantially addressed through reconstructed-kit methodology.
The remaining research questions are now genealogical rather than genetic: identifying which specific ancestral couples in pre-Famine Donaghmoyne connect the four documented founding couples to one another. The brother hypothesis (Henry, Owen, and James of Dian as siblings or close cousins) remains a reasonable working theory, now supported by segment-level corroboration in addition to documentary parish-marriage records and naming patterns. Resolving the specific relationships requires documentary research in pre-1830 Irish records.
This analysis represents BCG-standard genetic-genealogical research with published methodology. The chromosome 2 evidence base is documented at the Chromosome 2 Triangulation Analysis component page. Conclusions are subject to revision as additional evidence emerges.