TRPV4 and skeletal dysplasia: Worms with mutations in the TRPV4 homolog osm-9 lose responsiveness to mechanical stimuli (29), Trpv4 knockout mice are deficient in systemic and cellular responsiveness to osmotic and mechanical stress (29–31) and gain- and loss-of-function TRPV4 mutations cause retinal degeneration (32), sensory/motor neuropathies, and skeletal dysplasias (33, 34).