What are the genetic changes related to Ellis-van Creveld syndrome ?
Ellis-van Creveld syndrome can be caused by mutations in the EVC or EVC2 gene. Little is known about the function of these genes, although they appear to play important roles in cell-to-cell signaling during development. In particular, the proteins produced from the EVC and EVC2 genes are thought to help regulate the Sonic Hedgehog signaling pathway. This pathway plays roles in cell growth, cell specialization, and the normal shaping (patterning) of many parts of the body.  The mutations that cause Ellis-van Creveld syndrome result in the production of an abnormally small, nonfunctional version of the EVC or EVC2 protein. It is unclear how the defective proteins lead to the specific signs and symptoms of this condition. Studies suggest that they prevent normal Sonic Hedgehog signaling in the developing embryo, disrupting the formation and growth of the bones, teeth, and other parts of the body.  Together, mutations in the EVC and EVC2 genes account for more than half of all cases of Ellis-van Creveld syndrome. The cause of the remaining cases is unknown.