(Photo: National Human Genome Research Institute/Public Domain)
A version of this story was originally published in the journal Limn.
The first “clearing house” for human genetic diversity data was established in 1951 in a small building at the back of the Royal Anthropological Institute in Bedford Square, London. There, at the Nuffield Blood Group Centre, a librarian, clerk, and statistician collated and ordered a vast paper archive of blood-group data, overseen by Arthur Mourant, a hematologist affiliated with the World Health Organization. At the time, blood groups were one of the very few human traits with clear genetic inheritance, and blood-group data was being abundantly produced in the context of blood transfusion.
The humble setting of Mourant’s clearing house belied its lofty ambitions. Announcing the new Centre, the U.S. magazine Science News-Letter claimed that blood-group data would offer nothing less than a new way of understanding human history and diversity, revealing "the genetic relationships of different groups of people" and making visible the "past nomadic wanderings and migrations of early human tribes over the face of the earth."
Mourant’s archival ambitions were made possible by his practices as head of the Blood Group Reference Laboratory a few miles down the road in the London borough of Chelsea. Blood groups are inferred by testing blood samples against antibodies (antisera) extracted from the blood of human donors; Mourant’s Reference Laboratory made and distributed standardized antisera to hospitals and transfusion centers around the world. Established in 1946 as part of Britain’s peacetime blood transfusion service, Mourant’s lab was designated the central blood-grouping laboratory of the WHO, which Mourant perceived to be a golden opportunity for the large-scale collation of blood-group data.
The brutality of the First World War had made people into resources for procuring blood, but the Second World War produced the conditions for the large-scale, centralized management of donors, which in turn became a plentiful resource for geneticists. Barely two months after recruitment to Britain's Emergency Blood Transfusion Service began, the Times announced that the service had registered its first 100,000 donors.
In the years following the end of the war, Britain’s Ministry of Health attempted to standardize—right down to the level of typography—the management of blood and people. As transfusion was scaled up, more and more blood groups were discovered, and the specificity of blood became a new focus of bureaucratic concern. With so many people on its registry the new, peacetime National Blood Transfusion Service had reliable supplies of the common blood types, and it became increasingly focused on donors with unusual blood. While the “search for rare blood” became a dramatic narrative theme in films, plays, and newspaper reports, Mourant—by then one of the principal authorities within the transfusion service—oversaw the production of a new bureaucratic technology: a nationwide “rare blood panel” comprising a list of 2,000 donors with the rarest blood types. If a hospital anywhere in the country needed rare blood for a patient, it would telephone Mourant’s laboratory in London and consult the nationwide panel for a match. Only with large numbers of registered donors in a standard nationwide service was the specificity of rare blood made visible.
The specificity of blood types became sharper as the donor registry became larger. Whereas in the 1920s a person could be A, B, AB or O, by 1950 a patient could be identified by six separate blood-group systems, of which perhaps only the Rhesus system has joined ABO in the popular understanding of blood. Mourant used this increased specificity in his anthropological archive: the greater the quantity of data he could accrue, the more detailed his geographic maps of human genetic diversity.
Around the same time, UNESCO endorsed the value of blood-group–based population genetics to an international public in a high-profile campaign to undermine racial prejudices. Blood-group gene frequencies – the argument went – affirmed the existence of biological differences between human populations, but also flattened and neutralized racial hierarchies: for UNESCO they were the perfect mediators of racial difference. Moreover, the kind of endeavor carried out by Mourant – to map blood-group frequency diversity and thereby produce a picture of human history – was highlighted as proof of the virtues of taking a population-genetic approach to race.
An Eldon card. (Photo: Limn)
Later that decade, the process behind blood collection also began to change. In the mid 1950s, Danish physician Knud Eldon invented a technology that combined blood with paper. Blood grouping using ‘Eldon Cards’ involved applying blood samples directly onto a card impregnated with antibodies. More widely enduring was the "Guthrie" card, invented in the early 1960s by US clinical microbiologist Robert Guthrie for testing newborns for the genetic condition phenylketonuria. Today, Guthrie Cards are still routinely used to collect the blood of newborns for an array of protein and genetic tests.
The 1960s saw even more technological change. First, blood was refracting into an array of new protein polymorphisms: techniques such as gel-electrophoresis (separating proteins using an electrical charge) revealed hemoglobin and enzyme variants that were, like blood groups, genetically inherited. And human chromosome preparations—also made from extracted blood—gradually became a compelling new area of research. Second, novel technologies of cold storage had made possible a new material form: the freezing of blood samples. Whereas in the 1940s blood-grouping tests had been possible only on freshly extracted blood, now protein polymorphisms could be resolved from freezeable samples. And not only known genetic variation: frozen serum was stable enough to be kept for genetic tests that might be discovered in the future. Now blood itself, with its apparently unlimited potential, could be archived in frozen form, prompting enterprises such as the large-scale blood collection projects of the International Biological Programme. The decades-long medical pursuit for a reliable supply of blood, in other words, was over. Now all scientists had to do was study it.