Frontonasal dysplasia is a rare condition that results from abnormal development of the head and face before birth. Individuals with this condition have at least two of the following physical features:
Other features may include other eye abnormalities (coloboma, cataract, microphthalmia), hearing loss, and/or agenesis of the corpus callosum. Some individuals may have intellectual disability. There are at least three types of frontonasal dysplasia that are distinguished by their genetic causes and their signs and symptoms.
Mutations in the ALX3 gene cause frontonasal dysplasia type 1. Mutations in the ALX4 gene cause type 2. Type 3 is caused by mutations in the ALX1 gene. When frontonasal dysplasia is caused by mutations in the AXL1 or AXL3 gene, it is inherited in an autosomal recessive fashion. Mutations in the AXL4 gene are inherited in an autosomal dominant fashion. Treatment of the condition depends on the severity of the signs and symptoms and may include one or more surgical procedures as well as special social, educational and medical services.
The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.
|Signs and Symptoms||Approximate number of patients (when available)|
|Median cleft lip||50%|
|Midline defect of the nose||50%|
|Aplasia/Hypoplasia of the corpus callosum||7.5%|
|Camptodactyly of finger||7.5%|
|Clinodactyly of the 5th finger||7.5%|
|Conductive hearing impairment||7.5%|
|Low-set, posteriorly rotated ears||7.5%|
|Preauricular skin tag||7.5%|
|Single transverse palmar crease||7.5%|
Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.
Nonprofit support and advocacy groups bring together patients, families, medical professionals, and researchers. These groups often raise awareness, provide support, and develop patient-centered information. Many are the driving force behind research for better treatments and possible cures. They can direct people to research, resources, and services. Many groups also have experts who serve as medical advisors. Visit their website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD. Suggest an organization to add.
These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.
The following diseases are related to Frontonasal dysplasia. If you have a question about any of these diseases, you can contact GARD.