A Protein Runs In Nine Families. ‘Notice What I Just Did.’
Serology from four continents finds a variant protein in 41 people, all descended from one line. Every explanation for it is ordinary — and the alternative reading is a blood libel with a new coat of paint.
A months-long reporting project. Documents cited below are held in The Vault and available to readers.
LEIDEN, Netherlands — Forty-one people carry it. All forty-one descend from one couple who married in Zeeland in about 1644.
The protein is real. Dr. Machteld Vanderkooij-Rasheed found it, published her protocol before she ran a single sample, and has since been asked about it by more journalists than she has published papers.
What it does is nothing anybody can measure.
What was found
A variant of a membrane protein, present in 41 of 610 tested relatives across nine documented family lines, and in none of 4,100 controls.
Read that sentence again, because two-thirds of it is the part that gets dropped. Five hundred and sixty-nine relatives of these carriers do not have it. It is not universal even inside the families. It is a variant that runs in a pedigree the way a great many variants run in a great many pedigrees.
The ordinary explanation
Professor Kwabena Osei-Lindqvist has spent his career on founder effects and was, in his own word, "bored" by the question.
A small population. A geographically isolated province. High marriage-within rates — 71 per cent in 1820, falling to 24 per cent by 1950, both figures from the public registers. One couple in 1644 with an uncommon variant.
"That is the entire mechanism," he said. "It is in every undergraduate textbook. The Afrikaner populations, the Old Order Amish, the Finns, the Ashkenazim, Tristan da Cunha, the Faroese — all of them have variants like this, and every one of those populations has had somebody build a story about it."
He paused there, and asked to add something.
"Notice what I just did. I listed populations, and you started to feel that the list meant something. It does not. The list means those are the populations somebody bothered to study."
The thing this newspaper did before writing
We went to a historian of antisemitic blood conspiracy and asked her how a story like this gets used.
Rev. Dr. Ilse Brandt-Achebe was blunt. The structure — a hidden lineage, a marker in the blood, a family that is secretly a different kind of thing — is not a modern invention and does not become one because a serologist is involved. It is the oldest libel in Europe with a laboratory bolted to the front.
She did not tell us not to publish. She told us what to put in, and it is in.
What the families say
Six of the nine agreed to reply jointly. Their statement is printed in full at the foot of this story, ahead of anything we have to say, at their request.
It is the best-written thing in this newspaper this month and the only part of it our correspondent has read aloud in the newsroom.
Between the forty-one of them, they note, they own one holiday caravan.
The bound, not the proof
Our headline says the protein is found in nobody else. That is true of the 4,100 people we tested and it is not true of the world, and our standards editor has flagged the overreach in the comparison box below rather than letting it pass.
Four thousand one hundred is a very small number of humans. If the variant sits at one in fifty thousand, we would expect to find none in a sample this size even if a hundred and sixty thousand people carried it.
Dr. Vanderkooij-Rasheed put that number in her own paper's abstract, unprompted, which is why this newspaper trusts her arithmetic and prints it here.
"Every time somebody writes about this, they write 'found in nobody else'," she said. "I have stopped correcting it individually. I now just say the sample size, loudly, and hope."
The six o'clock edition
Three stories a morning, in your inbox before the coffee is made.
Sources & Method
Two genealogists reconstructed the pedigrees from public registers, independently, without seeing each other's work; where they disagree, both readings are printed. The serology protocol was published before the first sample. And before writing a word, this newspaper consulted a historian of antisemitic blood conspiracy about how a story like this gets misused, because a paper that reports on bloodlines without doing that is not being careful, it is being useful to somebody.
Who we spoke to
- Dr. Machteld Vanderkooij-Rasheed, Immunohaematologist, Leiden. Interviewed in person twice; ran the serology and published her protocol before starting March and June 2026
- Prof. Kwabena Osei-Lindqvist, Population geneticist. Interviewed by video call 2 July 2026 Gives the founder-effect explanation at length and is emphatic that it is boring.
- Representatives of six of the nine families, Speaking jointly. Written statement, prepared with their own solicitor and printed unedited July 2026 Three families declined to take part and their wish not to be contacted again has been recorded and honoured.
- Rev. Dr. Ilse Brandt-Achebe, Historian of antisemitic blood conspiracy. Interviewed in person 11 July 2026 Consulted before publication, at the reporter's request, on how this story could be misused. Her advice shaped the editor's note.
- Public parish, civil and probate registers, Netherlands, South Africa, Indonesia, Suriname. Read by two genealogists working independently 2026
Documents
- PX-1670 — Regional blood service — serological register, anonymised extract accepted
- PX-1944 — Reconstructed pedigrees, nine families, 1644–present — two independent genealogies accepted
What we could not confirm
- Whether the variant exists outside these families. We tested 4,100 controls and found none. That is a bound, not a proof; 4,100 is a very small number of humans.
- What, if anything, the variant does. It is a membrane protein of unknown function. Nobody in this story claims it does anything.
- The 1644 register entry. One of our two genealogists reads the founder pair's surname differently from the other, and both readings are printed.
How Others Covered This
The same events, as reported elsewhere on the same day. We list what each outlet had that we did not, as well as what we had that they did not — including where we come off worse. Why we print this.
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The Hollow PostTHE BLOODLINE IS REAL AND WE HAVE THE NAMES
Published a list of surnames. Two of the nine lines have since had journalists at the door.
Had that we did not
Nothing.
Left out
That 569 of 610 tested relatives do not carry it; that the founder-effect explanation is the one every geneticist in the story gives; and any attempt to reach the families.
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Signal & LedgerRare Membrane Variant Traced To Seventeenth-Century Founder Pair
Ran it as population genetics, correctly and without drama.
Had that we did not
A second geneticist we could not reach and a clearer account of linkage disequilibrium than ours.
Left out
The families' own view, which they have and which nobody asked for.
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They Buriedthis newspaperA Protein Runs In Nine Families And In Nobody Else
Reported the serology, the pedigree and the ordinary explanation together, and refused the version of this story that is an old libel.
Had that we did not
The families' statement, and the editor's note refusing the antisemitic variant.
Left out
Our headline says 'and in nobody else', which is true of the 4,100 controls tested and not of the world. That is a real overreach and the dek should carry it more plainly than it does. — V. Ashcombe-Doyle, standards editor
Right of Reply
They Buried contacted Six of the nine families, speaking jointly in April 2026, before any testing, through a solicitor of their choosing whose fee this newspaper did not pay. They asked to reply jointly and to be printed first, unedited, ahead of anything the newspaper had to say. They are.
We are farmers, teachers, two nurses, a bus driver and a retired harbour pilot.
We agreed to this because Dr. Vanderkooij-Rasheed asked us properly, three years ago, and explained what she wanted and what she could not promise. We did not agree to be a story. We understand that we have become one anyway and that this is nobody's fault but the internet's.
What we would like on the record is this. A protein is not a destiny. None of us runs anything. Between the forty-one of us we own one holiday caravan.
We have read what is written about people like us. We know exactly which older story it is wearing. Our grandparents knew that story too, and some of them did not survive people believing it.
So print the science if the science is interesting. Print our names never. And when somebody tells you this makes us something other than a large family from a small province, remember that we asked you, in writing, in advance, to say that it does not.
Published unedited under our right-of-reply guarantee.
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