Cleidocranial Dysplasia (cont.)
How common is cleidocranial dysplasia?
Cleidocranial dysplasia occurs in approximately 1 per million individuals
worldwide.
What genes are related to cleidocranial dysplasia?
The RUNX2 gene provides instructions for making a
protein that is involved in bone and cartilage development and maintenance. This protein is a transcription
factor, which means it attaches (binds) to specific regions of DNA and helps
control the activity of particular genes. Researchers believe that the RUNX2
protein acts as a "master switch," regulating a number of other genes involved
in the development of cells that build bones (osteoblasts).
Some mutations change one protein building block (amino acid) in the RUNX2
protein. Other mutations introduce a premature stop signal that results in an
abnormally short protein. Occasionally, the entire gene is missing.
These genetic changes reduce or eliminate the activity of the protein
produced from one copy of the RUNX2 gene in each cell, decreasing the total
amount of functional RUNX2 protein. This shortage of functional RUNX2 protein
interferes with normal bone and cartilage development, resulting in the signs
and symptoms of cleidocranial dysplasia. In rare cases, affected individuals may
experience additional, unusual symptoms resulting from the loss of other genes
near RUNX2.
In about one-third of individuals with cleidocranial dysplasia, no mutation
in the RUNX2 gene has been found. The cause of the condition in these
individuals is unknown.
How do people inherit cleidocranial dysplasia?
This condition is inherited in an autosomal dominant pattern, which means one
copy of the altered gene in each cell is sufficient to cause the disorder. In
some cases, an affected person inherits the mutation from one affected parent.
Other cases may result from new mutations in the gene. These cases occur in
people with no history of the disorder in their family.
Healthy Living Tips
Health News Feed
This site complies with the