What are the genetic changes related to Kuskokwim syndrome ?
Kuskokwim syndrome is caused by mutations in the FKBP10 gene, which provides instructions for making the FKBP10 protein (formerly known as FKBP65). This protein is important for the correct processing of complex molecules called collagens, which provide structure and strength to connective tissues that support the body's bones, joints, and organs. Collagen molecules are cross-linked to one another to form long, thin fibrils, which are found in the spaces around cells (the extracellular matrix). The formation of cross-links results in very strong collagen fibrils. The FKBP10 protein attaches to collagens and plays a role in their cross-linking.  A mutation in the FKBP10 gene alters the FKBP10 protein, making it unstable and easily broken down. As a result, people with Kuskokwim syndrome have only about 5 percent of the normal amount of FKBP10 protein. This reduction in protein levels impairs collagen cross-linking and leads to a disorganized network of collagen molecules. It is unclear how these changes in the collagen matrix are involved in the development of joint contractures and other abnormalities in people with Kuskokwim syndrome.