This essay reflects on the tension between standardization and the search for variation in the human genome. The stabilization of the human chromosome count in the 1920s was based on the consensus that “Whites,” “Negroes,” and “Japanese,” as well as women and men, had the same number of chromosomes. Yet the idea that there might be chromosomal differences between various groups of people was never quite abandoned. When in the mid-1950s the human chromosome number was revised from 48 to 46, the new count was tested in populations around the world. The description of the “normal human karyotype” that was negotiated in the 1960s was driven by the search for a standard against which the genetic variation revealed by the flurry of testing could be measured. And although the human genome project in the 1990s promised to provide the genetic blueprint that all humans shared, it has in fact led to an increased focus on the genetic variation that distinguishes the history, identity, and health outcomes of various human populations. Following concrete examples, this essay investigates the historically contingent quests that have been driving the search for common standards and variation, and the role Pacific and Indigenous populations have played in these endeavors. This essay is part of a special issue entitled Pacific Biologies: How Humans Become Genetic , edited by Warwick Anderson and M. Susan Lindee.

This paper examines how populations in a multiethnic cohort project used to study environmental causes of cancer in Hawai‘i have been reorganized in ways that have contributed to the racialization of the human genome. We examine the development of two central genomic data infrastructures, the multiethnic cohort (MEC) and a collection of reference DNA called the HapMap. The MEC study populations were initially designed to examine differences in nutrition as risk factors for disease, and then were repurposed to search for potential genomic risk factors for disease. The biomaterials collected from these populations became institutionalized in a data repository that later became a major source of “diverse” DNA for other studies of genomic risk factors for disease. We examine what happened when the MEC biorepository and dataset, organized by ethnic labels, came to be used, in conjunction with the data from the HapMap reference populations, to construct human population genetic categories. Developing theory on genomic racialization, we examine (1) how and why Hawai‘i became sited as a “virtual natural laboratory” for collecting and examining biomaterials from different ethnic groups, and the consequences of the transformation of those local Hawaiian ethnic groups into five racial and ethnic OMB categories meant to represent global continental groups for genomic studies. We then discuss (2) how this transformation, via the geneticists’ effort to standardize the study of genomic risk for disease around the globe, led to the construction of humans as statistical genetic resources and entities for genomic biomedicine and the human population genetics discipline. Through this transformation of populations and biorepositories, we argue (3) that the twenty-first century has seen the intertwining of “race,” “population,” and “genome” via large-scale genomic association studies. We show how “race” has become imbricated in human population genetics and genomic biomedicine. This essay is part of a special issue entitled Pacific Biologies: How Humans Become Genetic , edited by Warwick Anderson and M. Susan Lindee.