Berichte zur Wissenschaftsgeschichte, Volume 45, Issue 3, Page 332-343, September 2022.

The use of molecules and reactions as evidence, markers and/or traits for evolutionary processes has a history more than a century long. Molecules have been used in studies of intra-specific variation and studies of similarity among species that do not necessarily result in the analysis of phylogenetic relations. Promoters of the use of molecular data have sustained the need for quantification as the main argument to make use of them. Moreover, quantification has allowed intensive statistical analysis, as a condition and (...) a product of increasing automation. All of these analyses are subject to the methodological anxiety characteristic of a community in search of objectivity. It is in this context that scientists compared and evaluated protein and nucleic acid sequence data with other types of molecular data – including immunological, electrophoretic and hybridization data. This paper argues that by looking at long-term historical processes, such as the use of molecular evidence in evolutionary biology, we gain valuable insights into the history of science. In that sense, it accompanies a growing concern among historians for big-pictures of science that incorporate the fruitful historical research on local cases of the last decades. (shrink)

ArgumentThis paper analyzes the research strategies of three different cases in the study of human genetics in Mexico – the work of Rubén Lisker in the 1960s, INMEGEN's mapping of Mexican genomic diversity between 2004 and 2009, and the analysis of Native American variation by Andrés Moreno and his colleagues in contemporary research. We make a distinction between an approach that incorporates multiple disciplinary resources into sampling design and interpretation (unpacking), from one that privileges pragmatic considerations over more robust multidisciplinary (...) analysis (flattening). These choices have consequences for social, demographic, and biomedical practices, and also for accounts of genetic variation in human populations. While the former strategyunpacksfine-grained genetic variation – favoring precision and realism, the latter tends toflattenindividual differences and historical depth in lieu of generalization. (shrink)

This paper extends previous arguments against the assumption that the study of variation at the molecular level was instigated with a view to solving an internal conflict between the balance and classical schools of population genetics. It does so by focusing on the intersection of basic research in protein chemistry and the molecular approach to disease with the enactment of global health campaigns during the Cold War period. The paper connects advances in research on protein structure and function as reflected (...) in Christian Anfinsen’s The molecular basis of evolution, with a political reading of Emilé Zuckerkandl and Linus Pauling’s identification of molecular disease and evolution. Beyond atomic fallout, these advances constituted a rationale for the promotion of genetic surveys of human populations in the Third World, in connection with international health programs. Light is shed not only on the experimental roots of the molecular challenge but on the broader geopolitical context where the rising role of biomedicine and public health had an impact on evolutionary biology. (shrink)

Between December 14 and 20, 1965, the World Health Organization Scientific Group on Haemoglobinopathies and Allied Disorders metatthe Geneva agency's headquarters. The group comprised eight well-known physicians including Tulio Arends, a leading Latin American human geneticist from the Venezuelan Institute for Scientific Investigations. Others came from North America, Northern and Southern Europe, the Middle East and South East Asia, an array that reflected the delicate geopolitical equilibriums of postwar international health programs, but also the development of highly specialized biomedical research (...) around the globe. They elected Herman Lehmann, from the Abnormal Haemoglobin Research Unit of the Medical Research... (shrink)

The importance of viruses as model organisms is well-established in molecular biology and Max Delbrück’s phage group set standards in the DNA phage field. In this paper, I argue that RNA phages, discovered in the 1960s, were also instrumental in the making of molecular biology. As part of experimental systems, RNA phages stood for messenger RNA, genes and genome. RNA was thought to mediate information transfers between DNA and proteins. Furthermore, RNA was more manageable at the bench than DNA due (...) to the availability of specific RNases, enzymes used as chemical tools to analyse RNA. Finally, RNA phages provided scientists with a pure source of mRNA to investigate the genetic code, genes and even a genome sequence. This paper focuses on Walter Fiers’ laboratory at Ghent University and their work on the RNA phage MS2. When setting up his Laboratory of Molecular Biology, Fiers planned a comprehensive study of the virus with a strong emphasis on the issue of structure. In his lab, RNA sequencing, now a little-known technique, evolved gradually from a means to solve the genetic code, to a tool for completing the first genome sequence. Thus, I follow the research pathway of Fiers and his ‘RNA phage lab’ with their evolving experimental system from 1960 to the late 1970s. This study illuminates two decisive shifts in post-war biology: the emergence of molecular biology as a discipline in the 1960s in Europe and of genomics in the 1990s. (shrink)

In 1971, Günter Blobel and David Sabatini proposed a novel and quite speculative schematic model to describe how proteins might reach the proper cellular location. According to their proposal, proteins destined to be secreted from the cell contain a “signal” to direct their release. Despite the fact that Blobel and Sabatini presented their signal hypothesis as a “beautiful idea” not grounded in experimental evidence, they received criticism from other scientists who opposed such speculation. Following the publication of the 1971 model, (...) Blobel persisted in conducting experiments and revising the model to incorporate new data. In fact, over the period of 1975–1984, Blobel and colleagues published five subsequent schematic models of the signal hypothesis, each revised based on new laboratory evidence. I propose that the original 1971 model can be viewed as an epistemic creation. Additionally, analysis of the subsequent schematic diagrams over the period of 1975–1984 allows one to track Blobel’s changing conception of an epistemic object over time. Furthermore, the entire series of schematic diagrams presented by Blobel from 1971 to 1984 allow one to visualize the initial conception and subsequent reworking of a scientific theory. In 1999, Blobel was awarded the Nobel Prize in Physiology or Medicine for his work on the signal hypothesis, which was ultimately supported by experimental evidence gathered after the speculative model was published. (shrink)