Translating time: Challenges, progress, and future directions.

Mice are the dominant model system to study human health and disease. Yet, there is a pressing need to use diverse model systems to address long-standing issues in biomedical sciences. Mice do not spontaneously recapitulate many of the diseases we seek to study. Accordingly, the relevance of studying mice to understand human disease is limited. We discuss examples associated with limitations of the mouse model, and how the inclusion of a richer array of model systems can help address long standing issues in biomedical sciences. We also discuss a tool called Translating Time, an online resource (www.translatingtime.org) that equates corresponding ages across model systems and humans. The translating time resource can be used to bridge the gap across species and make predictions when data are sparse or unavailable as is the case for human fetal development. Moreover, the Translating Time tool can map findings across species, make inferences about the evolution of shared neuropathologies, and inform the optimal model system for studying human biology in health and in disease. Resources such as these can be utilized to integrate information across diverse model systems to improve the study of human biology in health and disease.