I received two genetic testing kits as gifts, and when I moved to California I was able to purchase 23andme, which as far as I understand was unavailable in Maryland because the medical information given out might be misused. In 2022 I posted updates from Ancestry.com and 23andme. Genographic totally disappeared in 2019; hopefully I have their best info.
Ancestry.com's "24% Scandinavian" finding compared to 23andme's ".4% Scandinavian" finding is an interesting discrepancy. Here's what I think is going on: whether to call that bit of my DNA Scandinavian, or to call it British, depends on what a service's definition of "British blood" is. Vikings raided and settled the coast of Great Britain ca. 500-1000 A.D. and had children with its natives. At first those children were called "half-Norse." How many generations needed to go by before their descendants could be called "full British"?
Celtic Britons were the first post-prehistoric people to inhabit Great Britain. Then, the Germanic Angles, Saxons, and Jutes arrived. Then, Norsemen raided the coast. Finally, the Normans (Norse Vikings, West Franks, and Gallo-Romans) invaded. Can testing distinguish French blood from Franks intermarrying with 'native' Brits ca. 1066? Possibly not. At some point Britain (or Europe, or the world) is forced out of old racial taxonomies, at least in terms of genealogy.
Genetic testing engenders identity concepts -- concepts of "self". This is not always good practice. Proceed with caution.
Area of focus: national ancestry. A mix around the North Sea, pointing at British/Viking intermingling taking place between the Romans and the Norman Invasion. King Cnut is my spirit animal and Jethro Tull - "Broadsword" is my anthem.
Area of focus: medical. I like 23andme, but that might be cognitive bias (it was harder to obtain). I am big in Neanderthal (oop oop). I was not found to be a carrier for any genetic disorders. It is worth noting that 23andme best matches the last names on my family tree.
Area of focus: migration. Genographic's report included "Mediterranean" and "Southwest Asian" in high percentages. Southwest Asia is not Europe, but the people who would come to fall under the biogeographic label "European" passed through Southwest Asia on their way to Europe and the British isles, beginning their trip, ultimately, about 45 minutes West-South-West of Pretoria.
[barnacle] my 23andme says i come from county cork
[barnacle] in part
[barnacle] but mostly LONDON
[barnacle] basically i am german-english
[barnacle] and the english is flavored with irish and norse
[barnacle] and the german is flavored with french
[barnacle] kinda borderline in those ways
[barnacle] and really the english side is pre-revolutionary USA
[barnacle] hicks in VA and TN
The Neanderthal thing is problematic (perhaps especially in concert with the apeman silhouette): I've heard of (not accessed and read myself) internet posts about some kind of Neanderthal oppression awareness or etc, and it's not clear if this a joke or not, like so much online. But I can imagine convincing near future sci-fi about discrimination based on having more Neanderthal material -- even if it's only 2.4% vs 2.1%.