Running head: Mouse models in endocrine research Corresponding author:

Genetically modified mouse models have been used widely to advance our knowledge in the field of endocrinology and metabolism. A number of different approaches to generate genetically modified mice are now available, which provide the power to analyze the role of individual proteins in vivo. However, there are a number of points to be considered in the use and interpretation of these models. This review will discuss the advantages and disadvantages involved in the generation and use of different genetically modified mouse models in endocrine research, including conventional techniques (e.g. overexpression, knockout and knock-in models), tissue and/or time specific deletion of target genes (e.g. Cre-loxP and siRNA transgenic approaches), and gene-trap approaches to undertake functional genomics. This review also highlights the many factors that should be considered when assessing the phenotype of these mouse models, many of which are relevant to all murine physiological studies. These approaches are a powerful means by which to dissect the function of genes, and are revolutionizing our understanding of endocrine physiology and metabolism