Ancient British Isles
Shared DNA Segments
Analyzing your genetic similarity to ancient British reference samples...
Preparing your genetic-similarity report
Shared DNA Segments
Segments of DNA you share with ancient individuals (identity-by-descent). Sharing indicates a population-level genetic connection, not a named common ancestor.
From the first hunter-gatherers who followed the retreating ice to the Norman kings who reshaped a kingdom, the British Isles have always been a crossroads of peoples.
All segment matches
Select a row to see where on your chromosomes the shared segments fall.
Most shared DNA
Shared DNA per individual
Match confidence
Reading shared segments
What a centimorgan (cM) measures
A centimorgan is a unit of genetic length. Longer and more numerous shared segments indicate a stronger genetic connection between your DNA and an ancient individual's DNA at the population level.
Why confidence varies
Ancient DNA is often incomplete. Confidence reflects how many markers could be compared with each individual. Low-confidence matches rest on fewer shared markers and should be read with more caution.
Why segment sizes matter
Across thousands of years, shared DNA is broken into many short pieces. Short segments are common between people from related populations; longer segments are rarer and more informative. Neither indicates a specific named ancestor.