Race in a genome: long read sequencing, ethnicity-specific reference genomes and the shifting horizon of race.

The sequencing of the human genome at the turn of the 21st century was hailed as revealing the overwhelming genetic similarity of human groups. Scholars of genomics have critiqued the subsequent persistence of race-based genetic science, but were reassured that the wide availability of gene sequencing would end the use of race as a proxy for genetic difference. Once an individual's whole gene sequence could be read, they hoped, their ethnoracial classification would become redundant. At the same time, genome science was recognising that the differences between human genomes went beyond the genome sequence to the structure of the genome itself. 'Structural variation' between genomes, including insertions, deletions, translocations, inversions, and copy number variations, mean that the 'universal' reference genome used for genome sequencing is not so universal. As conventional, 'short-read' sequencing wrongly assumes that all genomes have the same structure, significant genetic variation can be missed. This paper examines the twin phenomena that have been posed as a solution to the biases of short-read sequencing: 'long-read' sequencing and 'ethnicity-specific reference genomes'. Long-read sequencing is a method of generating a genome sequence that can be assembled de novo rather than relying on the reference genome. In recent years, a number of countries including China, Korea, and Denmark have used long-read sequencing and de novo assembly to develop 'national' reference genomes. Our analysis of one ethnicity-specific reference genome project, the Korean Reference Genome (KOREF), finds that it unduly emphasises the importance of population structural variation, framed in nationalist terms, and discounts the importance of individual structural variation. We argue that the intellectual labour required to make a Korean reference genome a coherent concept works to extend the horizon of race, prolonging the temporality of the 'meantime' in which race remains a seemingly valid concept in genomic science.