Thread by @AdamRutherford

The deaths of 17 medieval Jews: An incredible new genetics paper has just dropped: The earliest Jewish genomes and the story of where they are from and how they died is incredibly important, and central to the origin of contemporary antisemitic conspiracy hatred. 🧵

This is (like the lactose/milk paper last month) is another barnstorming piece of #totalscience led by @mt_genes, Ian Barnes (@NHM_London) and also @Boothicus et al,
Here’s the paper itself
bit.ly/3pYd0sl

In 2004, builders working on the Chapelfield shopping centre in Norwich, UK, uncovered the mortal remains of what turned out to be 17 individuals in a medieval well.

The presence of that many skeletons, many children, some with head injuries and some head first, strongly indicates they were deliberately thrown in the well in a murderous or violent act. Radiocarbon dating puts the incident securely between 1161–1216 CE.

This date aligns with a prominent mass murder in Norwich in 1190CE when many Jewish people were killed during antisemitic riots, following the beginning of the Third Crusade.

In 1144, Norwich had been the setting for a foundational event in the history of antisemitism when the family of a boy – canonised as St. William of Norwich - claimed that local Jews had murdered him: this became the first documented invocation of the hideous Blood Libel myth.

This antisemitic conspiracy theory persists today, its origins lie within the soil of Norwich. The bodies in the well present a unique opportunity to assess the roots of this contemporary racism.

The origin of Ashkenazi Jews is complex and not well understood, but present-day Ashkenazi Jews are primarily descended from multiple diasporas who settled in various parts of Europe through the medieval period, and endured persecution throughout this period.

The Norwich bones are the oldest examples of Ashkenazi-associated DNA discovered – shown in the plot below. <IRONY KLAXON> this technique, PCA, was invented by Karl Pearson (of the same UCL department as @mt_genes and me), one of the most virulently antisemitic eugenicists ever.

The DNA of all six of the individual analysed were dissimilar to present-day British and northern Europeans. Instead, they partially overlap with Southern Europeans, close to Cypriots, modern Ashkenazi, Turkish, and North African Jews.

Other things we can glean from the DNA: They were closely related, three of the victims were sisters. One – an infant boy – looks like he had blue eyes, and red hair - a common negative stereotype of Medieval Jews (it later became common to depict Judas as a ginge).

This brilliant study pushes back the date of Ashkenazi-associated genetic disease alleles to centuries earlier than previously hypothesised, and with it the origin of Ashkenazim. It also helps us to understand a longstanding racist trope and religious persecution.

The victims of this religious persecution and crime were reburied in Earlham cemetery in Norwich in 2013.

These people were invited to England with William the Conqueror in 1066, worked, were persecuted, and expelled under the Edict of Expulsion issued by King Edward I on 18 July 1290 which banished all Jews from the Kingdom of England.

Anyway, a fascinating, landmark paper, which contextualises an important moment in history, a major medieval crime, and the origin of an antisemitic trope which persists today.

The authors are all awesome, the first 4 all equal contributors:
•@SelBrace
•Yoan Diekmann
•@Boothicus
•Ruairidh Macleod
•Adrian Timpson
•Will Stephen
•Giles Emery
•Sophie Cabot
•@mt_genes
•Ian Barnes

Corrigendum: William was never canonised, but was instead a local folk saint.

Addendum. The paper includes the identification of certain disease genes which occur at higher frequency in current Ashkenazi populations. This is important in refuting a popular, oft repeated but un-evidenced assertion about intelligence in Jewish people.

Since the surreally bad - but inexplicably popular - paper in 2006 'Natural History of Ashkenazi Intelligence' the assertion that higher frequency of the disease genes for Tay Sachs, Nieman Pick and Gaucher syndrome was a result of them bestowing heterozygous advantage.

That is, having one copy of the disease gene is associated with higher intelligence, even though two copies is lethal. This is the case for Sickle Cell trait (one copy, protective against Malaria), and disease (two copies, terrible disease).

They suggested that this selection occurred during the last several centuries in response to the profession of money lending, which Jews were permitted to do. However, the new study shows that these disease genes were present much earlier.

@mt_genes et al show that there was a genetic bottleneck that predates the Norwich massacre, and that is much more likely to account for the higher frequency of disease genes. A population shrinkage, combined with endogamy.

Genetics beats racism AGAIN.

Thanks to @smaceachern2 for reminding me of this, which I wrote about in How to Argue With a Racist.