What are the genetic changes related to X-linked chondrodysplasia punctata 1 ?
X-linked chondrodysplasia punctata 1 is caused by genetic changes involving the ARSE gene. This gene provides instructions for making an enzyme called arylsulfatase E. The function of this enzyme is unknown, although it appears to be important for normal skeletal development and is thought to participate in a chemical pathway involving vitamin K. Evidence suggests that vitamin K normally plays a role in bone growth and maintenance of bone density.  Between 60 and 75 percent of males with the characteristic features of X-linked chondrodysplasia punctata 1 have a mutation in the ARSE gene. These mutations reduce or eliminate the function of arylsulfatase E. Another 25 percent of affected males have a small deletion of genetic material from the region of the X chromosome that contains the ARSE gene. These individuals are missing the entire gene, so their cells produce no functional arylsulfatase E. Researchers are working to determine how a shortage of arylsulfatase E disrupts the development of bones and cartilage and leads to the characteristic features of X-linked chondrodysplasia punctata 1.  Some people with the features of X-linked chondrodysplasia punctata 1 do not have an identified mutation in the ARSE gene or a deletion involving the gene. Other, as-yet-unidentified genetic and environmental factors may also be involved in causing this disorder.