In France, the systematic neonatal screening for cystic fibrosis, a rare and incurable genetic disease, was instituted by the public authorities in 2002. Taking diagnosis disclosure as the departure point, our paper aims to reflect the singular and innovative configurations that have developed in the organisation of care (the creation of specific interdisciplinary care centres : Resource and Expertise Centres for Cystic Fibrosis), among professionals (concerning the roles and practices of doctors and nurses) and communication (dissemination of equivocal communication). The broader aim is to shed light on the transformations generated by this biomedical technology in a context marked by high risk medicine and the evolution of medical uncerta...