French-Canadians often find a few percent of "Jewish" ancestry in their DNA results, and many have heard family stories — a converso ancestor, a founder nicknamed "the Portuguese," a Middle Eastern haplogroup in the family. So we took nine founding lines of New France and asked their Y-chromosomes directly.
For each, we found the point on the Y-DNA tree where the family's branch meets the nearest branch carried by Jewish testers, and dated it.
The results
| Founder line | Y-haplogroup | Nearest Jewish branch meets it | Why it's undetermined |
|---|---|---|---|
| Savaria | E-PF2546 (E-M81) | ~2,100 years ago | Berber lineage; Jewish cousins expected |
| Vallière | T-BY50677 | ~3,000 years ago | node too deep |
| Coste | J-FT246510 | ~4,300 years ago | node too deep |
| Auger | J-Y4034 | ~4,300 years ago | node too deep |
| Gélinas | E-BY160511 (E-V13) | ~4,400 years ago | node too deep |
| Savard | E-Y31608 (E-M34) | ~5,400 years ago | node too deep |
| Boucher | E-L793 (E-M34) | ~5,600 years ago | node too deep |
| Amiot | J-FTA38287 (J2) | ~6,600 years ago | node too deep; sparse branch |
| Rodrigue dit Portugais | E-BY1098 (E-M34) | cannot be measured | test not detailed enough |
Nine lines, nine "undetermined." That isn't the method failing. It's the method working — and the reasons differ in ways that matter.
Four kinds of "undetermined"
1. The node is too deep. For six lines, the nearest Jewish relative on the tree shares an ancestor who lived between about 3,000 and 6,600 years ago. At that depth the Y-chromosome describes the Bronze or Stone Age, not a medieval family. More testing won't change it.
2. The branch is too sparse. Amiot's branch has very few testers and a 2,350-year gap in the tree with nothing in it. The answer could still move, but only by very little.
3. The lineage explains its own Jewish cousins. Savaria has the most recent meeting point of all, around 100 BCE, with a Libyan Jewish tester. But the branch is E-M81, the main paternal lineage of the Berber peoples of North Africa, and that Jewish tester's closest relative is a Moroccan Berber. North African Jewish communities absorbed Berber families over many centuries, so finding Jewish members inside E-M81 is expected. The shared ancestor was most likely a North African, not a Jew.
4. The test isn't detailed enough. Jean Rodrigue dit Portugais has the best documentary clue in all of New France: a recorded nickname meaning "the Portuguese." But his line's published haplogroup, E-BY1098, is a node about 5,800 years old with many branches below it. We can't tell which branch he belongs to, so we can't run the test at all.
What did come back positive
Geography. The testers on Simon Savard's branch are all from Seine-Saint-Denis — the département that contains Montreuil, where he was born in 1625. Marin Boucher's branch includes a tester from the Orne, where Mortagne-au-Perche lies. In both cases the Y-chromosome independently confirmed the documented French origin of the family.
That's a real result. The haplogroup confirmed where these families came from. It just didn't say who they prayed with.
A marker Jews carry isn't evidence you're Jewish
Several of these lines sit in branches that do contain Jewish testers. That's where the reasoning most often goes wrong. Some Jews carry E-M34, E-M81 and J2 — but so do huge numbers of non-Jews, and the fact that a group carries a marker doesn't mean the marker points to that group. The question is always how recently you meet, never whether a Jewish name appears somewhere downstream.
The one test worth paying for
If you descend in the male line from Jean Rodrigue dit Portugais, a detailed Y-DNA test (a Big Y-700 or similar) is probably the most valuable single test in French-Canadian genealogy. There's a strong document, a lineage in which Jewish branches do occur, and nearly six thousand years of tree to refine. One test could turn the best nickname in New France from a story into a date.
For everyone else: the next step isn't another DNA test. It's the parish and notarial records of the family's French origin.
Sources
- YFull YTree (v14.05.00, August 2026) and FamilyTreeDNA Discover, checked September 2026
- Programme de recherche en démographie historique (PRDH) and standard New France genealogies for founder origins