Dr Chrissy Hammond spoke about using zebrafish as an unusual animal model for studying the genetics of osteoarthritis; discussing both its advantages and limitations as a model system joint biology. The major advantages come from the ability to make transgenic lines; to both manipulate gene expression and to express fluorescent reporters. Her lab have made a number of cartilage and bone reporter lines, which in the optically translucent fish allow the dynamic visualisation of individual cells in the context of a functioning joint. In mutants with altered proteoglycan synthesis the timing of chondrocyte maturation is perturbed. In addition, Finite Element models, showing the strains operating on the joint, have been developed and these show that increased Wnt signalling activity is seen in the areas of the joint that are under the highest strain.