also been identified in zebrafish and mice. Although dogs, mice, fish, and humans are not genetically identical, some of these animal models have been officially recognized to represent the varying types of OI in humans. For example, homozygous oim/oim mice experience spontaneous bone fractures, small body size, and kyphosis, making them a model of OI type III. Meanwhile, heterozygous oim/+ mice appear normal but have bones which are quite a bit weaker than wild mice, making them a model for OI type I. As in human OI, the location on the gene which is mutated affects the severity of resulting disease—the G859C Col1a1 mouse is a model for OI type II as affected mice all die in the perinatal period. Animal testing on identified animal models may lead to human therapies for OI. Explanatory notes References External links Abnormalities of dermal fibrous and elastic tissue Skeletal disorders Collagen disease Rare diseases Wikipedia medicine articles ready to translate