This article addresses how people who handle transgenic animals in practice—laboratory workers and members of animal ethics committees—talk about and handle dilemmas with transgenic animals. It is shown how dilemmas associated with transgenic animals become back-grounded through rhetorical comparisons with ‘something else’. Through these comparisons, transgenic animals are framed as normal, ordinary and thereby unproblematic on the one hand, and as valuable treasures in which are embedded hopes and expectations of future medical treatments on the other. This tension builds up to a discourse on transgenic mice as ordinary treasures. Towards the end of the article we discuss how this discourse tends to exclude possibilities of discussing specific dilemmas of genetically modified animals. Instead the discourse is contributing to certain transgenic silences. This article is based on the project ‘Dilemmas with transgenic animals’, in which notions of culture and nature, risk and safety, innovation and organism, science and technology, are investigated in the scientific production, use and ethical evaluation of transgenic animals. The project builds on case studies in two different contexts: laboratories and animal ethics committees. The methods used are interviews and ethnographic fieldwork.