Otopalatodigital (OPD) spectrum disorders are a group of disorders that cause abnormal bone development that affects the ears (oto), roof of the mouth (palato), and fingers or toes (digital). The disorders in this spectrum include otopalatodigital spectrum disorders 1 and 2, frontometaphyseal dysplasia, Melnick-Needles syndrome, and terminal osseous dysplasia. Features that can be seen in these conditions include hearing loss, an opening on the roof of the mouth (cleft palate), finger and toe abnormalities, and unique facial features. Each condition has its own set of symptoms and features. More information about each of these diseases can be found under its own description entry in the Disease InfoSearch database.
All OPD spectrum disorders are due to a change (mutation) to the FLNA gene, which provides instructions for the body to make a protein called filamin A that is important for bone development. Because the FLNA gene is located on the X-chromosome, all of the OPD spectrum disorders are inherited in an X-linked dominant way. Males have only one X chromosome (one copy of the FLNA gene) while females have two X chromosomes (two copies of the FLNA gene). Males with a mutation in their only copy will have features of an OPD spectrum disorder that are more severe than females, since females will have a second copy of the gene that does not have a mutation.
A diagnosis of an OPD disorder is considered when a person has bone abnormalities, hearing loss, or other specific features of an OPD spectrum condition. Genetic testing can be used to confirm a diagnosis. Treatment options depend on the features of the disorder, but they can include hearing aids and surgery. If your child has been diagnosed with an OPD spectrum disorder, talk with their doctor about all treatment options. Support groups are also a good source of information.