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|
Early and severe mental retardation
Mental retardation, severe
Severe mental retardation[ more ]
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference[ more ]
Repetitive or self-injurious behavior[ more ]
|30%-79% of people have these symptoms|
|Abnormality of the dentition||
Dental abnormality[ more ]
|Abnormality of the metacarpal bones||
Abnormality of the long bone of hand
|Cerebral cortical atrophy||
Decrease in size of the outer layer of the brain due to loss of brain cells
Abnormal curving of the spine
Decreased body height
Small stature[ more ]
Involuntary muscle stiffness, contraction, or spasm
|5%-29% of people have these symptoms|
|Abnormality of the antihelix||0009738|
Abnormal heart rate
Heart rhythm disorders
Irregular heart beat
Irregular heartbeat[ more ]
|Arthrogryposis multiplex congenita||0002804|
|Clinodactyly of the 5th finger||
Permanent curving of the pinkie finger
|Decreased muscle mass||
Loss of developmental milestones
Mental deterioration in childhood[ more ]
|Failure to thrive||
Weight faltering[ more ]
Stiff joints[ more ]
Paralysis of all four limbs
|Percent of people who have these symptoms is not available through HPO|
Progressive dementia[ more ]
Acid reflux disease
Heartburn[ more ]
|Intellectual disability, profound||
IQ less than 20
Round back[ more ]
Progressive degeneration of movement
|Prolonged QTc interval||0005184|
Small feet[ more ]
|Skeletal muscle atrophy||
Muscle wasting[ more ]
The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your 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.
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
Differential diagnosis includes autism and Angelman syndrome; cataract, retinopathy, or optic atrophy; history of perinatal or postnatal brain damage; confirmed inborn error of metabolism or neurodegenerative disorder; acquired neurological disorder due to severe head trauma or infection. Storage disorder is usually excluded by the presence of organomegaly.
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.
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
How many Americans are diagnosed with Rett syndrome? See answer
I am a nurse, and I have a patient that presents with some of the classic signs of Rett syndrome. I want to locate a specialist in Rett syndrome genetics. Could your agency send me a list of practicing physicians and clinics with expertise in this area? See answer
Is it normal for girls with Rett syndrome to scream and cry? Can girls with Rett syndrome be potty trained? Also, is biting other children normal for girls with Rett syndrome? See answer
My friend's 3-year-old daughter was just diagnosed with Rett Syndrome. A boy sibling was born last week, and he does not have Rett syndrome. Where can we find more information? How do you become part of a clinical trial? See answer