With the launch of the Precision Medicine Initiative (PMI) in January 2015, the White House granted a high degree of federal support to an emerging biomedical paradigm. What explains this level of political recognition? Based on literature and policy analysis, we reconstruct the scientific and the legislative paths that led to the political endorsement of precision medicine. First, we describe the proliferation of personalized approaches to therapy ignited by the discovery of hemoprotein cytochrome P450 polymorphism in 1988. Then, we analyze the legislative history of precision medicine, from the unsuccessful introduction of Genomics and Personalized Medicine Acts in the second half of the last decade, to the highly acclaimed PMI. However, scientific progress and political contingency alone do not explain the upheaval of precision medicine as an institutionally supported initiative. On examination, the launch of a Precision Medicine Research Cohort and the incorporation of a participatory ethos into the fabric of the PMI proved to be crucial determinants of the political support for precision medicine. Weaving together the scientific and legislative antecedents of precision medicine, we illuminate how the mutual constitution of science and social order generates political recognition for innovative biomedical paradigms.