In 1997, researchers from Oxford University led by Professor Bryan Sykes took DNA from the pulp cavity of one of Cheddar Man’s molars and analyzed it at the Institute of Molecular Medicine. The analysis focused on mitochondrial DNA — the genetic material found in cellular structures called mitochondria, which is inherited exclusively through the maternal line and mutates at a relatively predictable rate over generations. Mitochondrial DNA analysis is useful for tracing matrilineal ancestry across long periods, though it describes only one line of descent and cannot characterize the full genetic heritage of an individual.
The Oxford researchers compared the mitochondrial DNA extracted from the tooth against samples from twenty local residents whose families had lived in the Cheddar area for several generations. The comparison found a match.
The matched individual was Adrian Targett, then 42 years old, a history teacher at King of Wessex Community School in Cheddar. Targett and Cheddar Man, the analysis suggested, shared a common matrilineal ancestor — a woman who had lived somewhere in the lineage connecting them across the intervening ten thousand years.
The finding attracted considerable media attention, partly because of its apparent human interest: a schoolteacher in the same Somerset town was, by this measure, a distant relative of the man in the limestone cave. The story ran in newspapers across the world.
It was also, in scientific terms, a relatively modest result. Mitochondrial DNA haplogroup matching of the kind the Sykes team performed can establish population-level connections — indicating that two individuals belong to the same broad matrilineal lineage — but it cannot establish direct genealogical relationship or quantify how closely related two people actually are. Cheddar Man’s mitochondrial haplogroup, U5b1, is found in a small percentage of modern Europeans; Targett’s shared haplotype made them members of the same maternal lineage, but the precise relationship — if there is any meaningful biological relationship at all, after ten thousand years of branching genealogy — cannot be stated precisely.