Normalization and the Search for Variation in the Human Genome

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.