A person with haplogroup W in nineteenth-century Europe could have had a maternal ancestry from virtually anywhere across a wide geographic range. The haplogroup identifies a maternal lineage going back tens of thousands of years to a common ancestral mitochondrial sequence; it does not identify a person’s country, region, or family.
The important comparison is not between haplogroup W and any geographic claim, but between haplogroup W and haplogroup H1bs — the Baden lineage. These two haplogroups diverged in the deep human past. They share no meaningful recent common ancestor within any genealogically relevant timeframe. A person whose maternal line belongs to haplogroup W cannot, without an intervening illegitimacy or error in the descent record, have a maternal ancestor who belongs to haplogroup H1bs, and vice versa.
Haplogroup H1bs — the haplogroup of the Baden maternal line, as represented by living descendants of Stéphanie de Beauharnais — is part of the large haplogroup H family, which dominates western European populations. H haplogroups are collectively found in the majority of western Europeans. H1bs is a specific subclade within this large group. The comparison between W and H1bs is a comparison between a rare lineage and a subclade of the most common European lineage. They are simply different.
This genetic background note matters because it establishes that the finding is not close or borderline. The difference between haplogroup W and haplogroup H1bs is not a subtle variation that could represent a distant relationship or a measurement artifact. These are distinct branches of the mitochondrial tree. The finding is unambiguous as a genetic result; the question the 2024 study addressed in depth was whether the samples genuinely belonged to Kaspar Hauser, and the answer to that question is the basis for the statistical confidence figure.