Abstract This article concerns the transformative potential of medical genomics for common disease research. We analysed 13 review articles in asthma research in the period 1999 to 2008. Our aim was to understand how genomics has emerged in this research field, and the attendant changes. Motivated by Lippman’s geneticisation thesis, we use the concept of an ‘innovation journey’ to trace how expectations of improved understanding, prevention, diagnosis and treatment structure a dynamic co-evolutionary process through which a genome-based discourse emerges. We show how the asthma researchers involved continuously struggle to define their contribution to asthma research, as well as to clinical practice. Along the way, the researchers propose changes to both the definition and the aetiological model of asthma, thus highlighting gene–gene and gene–environment interactions. It is, however, difficult to characterise this discourse as one of geneticisation. With increasing attention being given to epigenetics, metabolomics, proteomics and systems biology, the emerging picture suggests an important, but much less deterministic, role for genes.