In the field of science and technology studies, recent works have analyzed the multiplication of promises and predictions as a major evolution of science management. The authors involved in this "sociology of technical expectations" have documented the role played by promises in the elaboration of scientific projects and their impact on the social reception of scientific issues. Yet, little attention has been paid to the predictions regarding undesirable technological futures. This article proposes therefore to analyze the discursive and argumentative practices through which journalists, scientists, and politicians denounce and propose to counter a public issue "which does not exist yet": gene doping (no case of gene doping has been recorded to date). After a literature review of the field of the sociology of technological expectations and a presentation of the corpus, the article describes the structure of predictions and analyzes the discursive strategies according to which social actors predict a disaster in the making. The analysis is based on the study of media discourses about gene doping, in a corpus of 163 French language articles from European newspapers, published between 1998 and 2012.