Diabetes and "Defective" Genes in the Twentieth-Century United States

In the decades following the discovery of insulin, eugenicists grew concerned that more diabetics would survive into their reproductive years and contribute "defective" genes to the gene pool. Insulin thus came to be seen as both a blessing for the individual and a problem for the future of humankind. Nevertheless, diabetics in the United States were neither prevented nor discouraged from reproducing. I argue that this stemmed from the widespread belief that diabetes was a disease primarily of middle-class whites, who possessed positive traits that outweighed their particular genetic defect. Historians of eugenics have demonstrated convincingly that race and class stereotypes made some populations more vulnerable to coercive eugenic practices. The case of diabetes demonstrates that race and class stereotypes could also confer protection. In the end, possession of a defective gene mattered less than the perception of one's contribution to society.