This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
|Chronic otitis media||
Chronic infections of the middle ear
|Intellectual disability, moderate||
IQ between 34 and 49
Loosejointedness[ more ]
|Neurological speech impairment||
Speech impediment[ more ]
Flat foot[ more ]
|30%-79% of people have these symptoms|
|Attention deficit hyperactivity disorder||
Attention deficit disorder
Attention deficit-hyperactivity disorder
Childhood attention deficit/hyperactivity disorder[ more ]
Acid reflux disease
Heartburn[ more ]
Increased size of forehead
Elongation of face
Increased height of face
Increased length of face
Vertical elongation of face
Vertical enlargement of face
Vertical overgrowth of face[ more ]
Increased size of skull
Large head circumference[ more ]
Big lower jaw
Increased projection of lower jaw
Increased size of lower jaw
Large lower jaw
Prominent lower jaw[ more ]
Low or weak muscle tone
Decreased breadth of face
Decreased width of face[ more ]
Prominent ears[ more ]
|5%-29% of people have these symptoms|
Excessive, persistent worry and fear
|Ascending tubular aorta aneurysm||
Bulging of wall of large artery located above heart
|Cerebral cortical atrophy||
Decrease in size of the outer layer of the brain due to loss of brain cells
|Mitral valve prolapse||0001634|
Squint eyes[ more ]
|Percent of people who have these symptoms is not available through HPO|
|Abnormal head movements||0002457|
|Coarse facial features||
Coarse facial appearance
More active than typical
|Poor eye contact||0000817|
If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.
If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.
You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.
Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.
Conditions with similar signs and symptoms from Orphanet
The differential diagnosis includes other X-linked intellectual deficiencies, Sotos syndrome, microdeletion syndromes (e.g. 22q11.2 deletion syndrome), fetal alcohol syndrome (see these terms) or idiopathic autism.
Visit the Orphanet disease page for more information.
Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.
Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.
Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.
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.
Rare Disease Day at NIH 2021
March 1, 2021
Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question
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