Breton DNA
Genetic origins and closest populations · France · Western Europe
Brittany, the peninsula at the western tip of France, owes its Celtic language to migrants from south-western Britain who settled there in the 5th and 6th centuries AD, which is why Breton is a close relative of Welsh and Cornish. The genetic profile follows the same Atlantic link. In our model, Bretons are 46.2% steppe-related, 41.5% Anatolian Neolithic farmer and 12.3% Western hunter-gatherer, clearly more steppe than the French average (39.7%) and much closer to the British pattern. The closest ancient groups are medieval people from Cambridgeshire in England and Late Iron Age to Roman-era Durotriges from Dorset (both at distance 0.0166). After other Breton samples from Rennes, Brittany and Finistere, the nearest modern averages are Normans from Seine-Maritime (0.0159), then the Welsh (0.0163) and Cornish (0.0167), all closer than the French average, which does not appear among the ten nearest.
- Ancient components in our model: Steppe herders (Yamnaya) 46.2%, Anatolian Neolithic farmers 41.5%, Western hunter-gatherers 12.3%
- Closest population outside Brittany in our data: French Oïl (Normandy Seine-Maritime), distance 0.0159
- Closest ancient group in our data: England High-Late Medieval Cambridgeshire Hospital of St. John, distance 0.0166
Where does Breton DNA sit on the genetic map of the world? To answer, we take the averaged Global25 (G25) coordinates of the Breton individuals sampled in France and compare them with deep ancestral reference populations, with other modern groups and with ancient genomes. It is one of 335 populations in our atlas.
Ancient make-up of the Breton average
The ancient make-up of the Breton average is led by Steppe herders (Yamnaya) (46.2%), followed by Anatolian Neolithic farmers (41.5%) and Western hunter-gatherers (12.3%). The Steppe herders (Yamnaya) component reflects the Bronze Age herders of the Pontic-Caspian steppe (Yamnaya and related groups), whose ancestry spread across Europe and into Asia from about 3000 BC. The Anatolian Neolithic farmers share (41.5%) reflects the Neolithic farmers of Anatolia, who carried agriculture into Europe from about 6500 BC.
The fit is loose (fit distance 0.044), which usually means that none of the available reference populations is a close stand-in for part of this ancestry, so read the percentages as rough. The model draws on West Eurasian ancient genomes, with modern West African and East Asian stand-ins.
France Profonde – French Regional Ancestry Report
Closest modern populations to Breton
Genetically, the Breton average sits nearest to Breton (Ille-et-Vilaine Rennes) at 0.012, French (Brittany) at 0.012 and France (Brittany, N=17) at 0.014. On our scale, a distance of 0.012 counts as very close. Leaving aside the other regional samples listed under the same name in the G25 sheet, the nearest other populations are French (Brittany) (0.012), France (Brittany, N=17) (0.014) and French Oïl (Normandy Seine-Maritime) (0.016). Even the tenth closest, English, is only 0.018 away: Breton belongs to a dense cluster of related populations, so small differences inside that cluster should not be over-interpreted.
| # | Population | Distance | Closeness |
|---|---|---|---|
| 1 | Breton (Ille-et-Vilaine Rennes) | 0.0119 | Very close |
| 2 | French (Brittany) | 0.0120 | Very close |
| 3 | France (Brittany, N=17) | 0.0135 | Very close |
| 4 | Breton (Finistere) | 0.0152 | Very close |
| 5 | French Oïl (Normandy Seine-Maritime) | 0.0159 | Very close |
| 6 | Welsh | 0.0163 | Very close |
| 7 | Cornish | 0.0167 | Very close |
| 8 | English (Cornwall) | 0.0175 | Very close |
| 9 | Belgian (group A) | 0.0179 | Very close |
| 10 | English | 0.0181 | Very close |
Distances are Euclidean distances between averaged G25 coordinates. On our scale, below 0.025 is very close, below 0.050 close, below 0.080 moderate, and beyond that distant.
Closest ancient populations to Breton
If we search ancient DNA for the best match to Breton, England High-Late Medieval Cambridgeshire Hospital of St. John (High to Late Medieval, c. 1000-1500 AD) comes first, at 0.017, with England LIA-Roman Empire Durotrigian next. That is a very close match, which suggests strong genetic continuity between those ancient people (or close relatives of theirs) and the modern population. A close ancient match is not proof of direct descent: it means those individuals carried a similar overall mix of ancestry.
| # | Ancient sample or group | Period | Distance |
|---|---|---|---|
| 1 | England High-Late Medieval Cambridgeshire Hospital of St. John | High to Late Medieval, c. 1000-1500 AD | 0.0166 |
| 2 | England LIA-Roman Empire Durotrigian | Roman era, c. 1-400 AD | 0.0166 |
| 3 | England Early-High Medieval Cambridgeshire Cherry Hinton | Early to High Medieval, c. 500-1300 AD | 0.0167 |
| 4 | Sweden Early-High Medieval Viking Age Skara (Western Euro Profile) | Viking Age, c. 800-1050 AD | 0.0168 |
| 5 | Belgium Late Medieval-Early Modern Holy Roman Empire Sint-Truiden (Northwest Euro Profile) | Late Medieval to Early Modern, c. 1300-1800 AD | 0.0169 |
| 6 | Belgium High Medieval Holy Roman Empire Sint-Truiden (Northwest Euro Profile) | High Medieval, c. 1000-1300 AD | 0.0171 |
| 7 | Belgium Late Medieval-Early Modern Holy Roman Empire Sint-Truiden (Western Euro Profile) | Late Medieval to Early Modern, c. 1300-1800 AD | 0.0173 |
| 8 | England Roman Empire-Late Antiquity | Late Antiquity, c. 250-600 AD | 0.0174 |
| 9 | Belgium Late Medieval Holy Roman Empire Sint-Truiden (Northwest Euro Profile) | Late Medieval, c. 1300-1500 AD | 0.0176 |
| 10 | France IA1 Hallstatt Hauts-de-France | Iron Age | 0.0178 |
Ancient DNA from France
Our ancient DNA database holds 1,113 individuals excavated in present-day France, dated from about 52,000 BC to 1821 AD. The most frequent Y-DNA haplogroups among them are R1b (163), I2a (144) and G2a (142), and the most frequent mtDNA haplogroups are K1 (131), U5 (116) and H1 (104). These are people who lived on the same land in the past, not necessarily ancestors of today's Breton population.
Most frequent Y-DNA haplogroups
Most frequent mtDNA haplogroups
Ancient DNA studies on France
- Ancient DNA Reveals Limited Hunter-Gatherer Ancestry in the Cerny Culture (Middle Neolithic, France) Despite Hunting-Associated Practices (2026)
- Population discontinuity in the Paris Basin linked to evidence of the Neolithic decline (2026)
- L’apport de la paléogénétique à la compréhension des populations de la fin de l’Antiquité et du début du Moyen Âge. L’exemple de la nécropole de la gare Saint-Laud à Angers (2025)
- Ancient DNA sheds light on the funerary practices of late Neolithic collective burial in southern France (2025)
- How local reference panels improve imputation in French populations (2024)
- Genomic ancestry and social dynamics of the last hunter-gatherers of Atlantic France (2024)
- Earliest evidence of human occupations and technological complexity above the 45th North parallel in Western Europe. The site of Lunery-Rosieres la-Terre-des-Sablons (France, 1.1 Ma) (2024)
- Late Neolithic collective burial reveals admixture dynamics during the third millennium BCE and the shaping of the European genome (2024)
Browse them in our ancient DNA database: 1,113 from France.
Compare yourself with Breton
Paste your G25 coordinates (scaled, one line, with or without a name in front) and we compute your genetic distance to the Breton average and to its closest neighbours, right in your browser. Nothing is uploaded or stored.
| # | Population | Your distance | Closeness |
|---|
This list only covers Breton and its neighbours. To find out which of our reports actually fits your DNA, run the free Report Finder: it runs the same fit test that every report uses before an order.
No G25 coordinates yet? Get a free simulated G25 from your raw DNA file, or order G25 coordinates.
About these numbers
A word of caution: these figures describe the average of the Breton individuals who were sampled, not every person who identifies as Breton. Individuals vary around that average, and identity is about history, language and family, not about a genetic score. Read this page as a map of deep ancestry, not as a definition.
Method: averaged G25 coordinates, Euclidean distances to other modern and ancient averages, and a non-negative least-squares model against deep ancestral reference populations (data generated 2026-10-01). Read the full method.
Go deeper than the average
This page describes the Breton average. Your own DNA has its own story: France Profonde – French Regional Ancestry Report (15€) models your genome against the ancient sources and modern communities of the region, era by era, in a personal PDF report.
A report built for people of French ancestry: ancient regional core (Gaulish, Frankish, Gallo-Roman, Norse Norman) versus non-regional outside admixture, across France's 20 historic regions (Alsace, Brittany, Normandy, Provence, Auvergne...
More populations from Western Europe
Frequently asked questions
What is the ancient genetic make-up of Breton?
Modelled with deep ancestral reference populations, the Breton average is about 46.2% Steppe herders (Yamnaya), 41.5% Anatolian Neolithic farmers and 12.3% Western hunter-gatherers. These proportions are model estimates for a group average, not exact values for any one person.
Which populations are genetically closest to Breton?
Leaving aside other regional samples listed under the same name in the G25 sheet (such as Breton (Ille-et-Vilaine Rennes)), the closest modern populations to the Breton average are French (Brittany), France (Brittany, N=17) and French Oïl (Normandy Seine-Maritime). The closest ancient matches are England High-Late Medieval Cambridgeshire Hospital of St. John, England LIA-Roman Empire Durotrigian and England Early-High Medieval Cambridgeshire Cherry Hinton.
Can a DNA test tell me if I am Breton?
No DNA test can confirm an ethnicity or a nationality. What DNA can show is how similar your genome is to the sampled Breton average and to its neighbours. If you have G25 coordinates, paste them in the comparison box on this page to check that for free.
Which ExploreYourDNA report suits Breton ancestry?
For the Breton average, the regional report to choose is France Profonde – French Regional Ancestry Report, which our fit test rates as an excellent match. Your own DNA may differ from the average, so the free Report Finder checks every report against your file before you buy.
Where does the data on this page come from?
From the averaged Global25 (G25) coordinates of the sampled individuals: genetic distances to other modern and ancient population averages, and a non-negative least-squares model against deep ancestral reference populations. The full method is described at https://www.exploreyourdna.com/populations#method.