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||
|Percent of people who have these symptoms is not available through HPO|
|Abnormality of eye movement||
Abnormal eye movement
Abnormal eye movements
Eye movement abnormalities
Eye movement issue[ more ]
Slowness of movements[ more ]
Abnormal deposits of calcium in the brain
Swallowing difficulty[ more ]
Increased body temperature, episodic
Intermittent fever[ more ]
|Excessive daytime somnolence||0001262|
Watery mouth[ more ]
Decreased muscle tone
Low muscle tone[ more ]
Onset in first year of life
Onset in infancy[ more ]
Mental retardation, nonspecific
Mental-retardation[ more ]
|Intellectual disability, progressive||
Mental retardation, progressive
Progressive mental retardation[ more ]
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference[ more ]
Low or weak muscle tone
|Muscular hypotonia of the trunk||
Low muscle tone in trunk
|Progressive neurologic deterioration||0002344|
|Severe muscular hypotonia||0006829|
|Small for gestational age||
Birth weight less than 10th percentile
Low birth weight[ more ]
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.
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.
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.
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.
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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