Disease Information

Summary

Mabry syndrome is a condition characterized by intellectual disability, distinctive facial features, increased levels of an enzyme called alkaline phosphatase in the blood (hyperphosphatasia), and other signs and symptoms. People with Mabry syndrome have intellectual disability that is often moderate to severe. They typically have little to no speech development and are delayed in the development of motor skills (such as sitting, crawling, and walking). Many affected individuals have low muscle tone (hypotonia) and develop recurrent seizures (epilepsy) in early childhood. Seizures are usually the generalized tonic-clonic type, which involve muscle rigidity, convulsions, and loss of consciousness. Individuals with Mabry syndrome have distinctive facial features that include wide-set eyes (hypertelorism), long openings of the eyelids (long palpebral fissures), a nose with a broad bridge and a rounded tip, downturned corners of the mouth, and a thin upper lip. These facial features usually become less pronounced over time. Hyperphosphatasia begins within the first year of life in people with Mabry syndrome. There are many different types of alkaline phosphatase found in tissues; the type that is increased in Mabry syndrome is called the tissue non-specific type and is found throughout the body. In affected individuals, alkaline phosphatase levels in the blood are usually increased by one to two times the normal amount, but can be up to 20 times higher than normal. The elevated enzyme levels remain relatively stable over a person's lifetime. Hyperphosphatasia appears to cause no negative health effects, but this finding can help health professionals diagnose Mabry syndrome. Another common feature of Mabry syndrome is shortened bones at the ends of fingers (brachytelephalangy), which can be seen on x-ray imaging. Underdeveloped fingernails (nail hypoplasia) may also occur. Sometimes, individuals with Mabry syndrome have abnormalities of the digestive system, including narrowing or blockage of the anus (anal stenosis or anal atresia) or Hirschsprung disease, a disorder that causes severe constipation or blockage of the intestine. Rarely, affected individuals experience hearing loss. The signs and symptoms of Mabry syndrome vary among affected individuals. Those who are least severely affected have only intellectual disability and hyperphosphatasia, without distinctive facial features or the other health problems listed above.

About Hyperphosphatasia-intellectual disability syndrome

Many rare diseases have limited information. Currently, GARD aims to provide the following information for this disease:

  • Symptoms:May start to appear as a Newborn and as an Infant.
  • Cause:This disease has more than one possible cause.
  • Organizations:Contact a GARD Information Specialist to help search for patient organizations dedicated to this rare disease.
  • Categories:GeneticdiseasesNeurologicaldiseasesInherited MetabolicdiseasesBirthdefects

Causes

What Causes This Disease?

Genetic Mutations


Can diseases be passed down from parent to child?

Autosomal Recessive

When Do Symptoms of Hyperphosphatasia-intellectual disability syndrome Begin?

Symptoms of this disease may start to appear as a Newborn and as an Infant.

The age symptoms may begin to appear differs between diseases. Symptoms may begin in a single age range, or during several age ranges. The symptoms of some diseases may begin at any age. Knowing when symptoms may have appeared can help medical providers find the correct diagnosis.
Prenatal
Before Birth
Newborn Selected
Birth-4 weeks
Infant Selected
1-23 months
Child
2-11 years
Adolescent
12-18 years
Adult
19-65 years
Older Adult
65+ years
Symptoms may start to appear as a Newborn and as an Infant.

Symptoms

The types of symptoms experienced, and their intensity, may vary among people with this disease. Your experience may be different from others. Consult your health care team for more information.

The following describes the symptom(s) associated with this disease along with the corresponding body system(s), description, synonyms, and frequency (Note: Not all possible symptoms may be listed):

58 Symptoms

58 Symptoms

58 Symptoms

Musculoskeletal System

The musculoskeletal system is made up of the bones, muscles, and joints. Common symptoms of problems in the musculoskeletal system include pain, weakness, stiffness, noises in the joints, inflammation, and decreased range of motion. Diseases affecting the musculoskeletal system may be diagnosed and treated by an orthopedist, rheumatologist, or neuromuscular specialist.

Navigating Health Care Decisions

On average, it can take more than six years to receive an accurate diagnosis. Many primary care providers (PCPs) may not be familiar with rare diseases, and patients often need to visit multiple specialists or seek second opinions to get answers.

If a diagnosis remains unclear, visiting a multidisciplinary care center or university hospital may help. These centers bring together teams of specialists who can work together to evaluate symptoms and coordinate a diagnosis. This team-based approach is also helpful after a diagnosis, when managing care for rare diseases.

Because only about 5% of rare diseases have FDA-approved treatments, finding the right healthcare team to manage your symptoms and overall health is essential. People living with rare diseases often face challenges such as delayed diagnosis, limited treatment options, and difficulty accessing knowledgeable providers. Building a care team that understands your needs can make a significant difference in your quality of life.

Your Health Care Team

Why is building the right health care team important?

Building the right health care team is key to the diagnosis, treatment, and management of your long-term health journey living with a rare disease. Start by choosing a primary care provider (PCP). Your PCP will be your main point of contact and help coordinate care with other medical professionals. Your PCP may order tests or refer you to specialists. To find a PCP near you, use the Medicare provider search tool and enter your location and “Primary Care Provider.”

Seeing multiple specialists is important for people with rare diseases because these conditions often affect many parts of the body and require care from doctors with different expertise. Most primary care providers may not be familiar with rare diseases, so involving specialists can lead to a more accurate diagnosis and better care. A coordinated team approach ensures that all symptoms are addressed and that care is well-managed. It can also connect patients with the latest research or treatment options.

A PCP that specializes in the care of children is called a pediatrician. Use this tool by the American Academy of Pediatrics to find a pediatrician in your area by inputting your location.
These specialists may help in the diagnosis, management, and treatment of Hyperphosphatasia-intellectual disability syndrome:
 

Multidisciplinary Care Centers

Is It Time to Get a Second Opinion or Specialized Evaluation?

If you've visited your PCP, met with specialists, and undergone the recommended tests, but are still searching for a diagnosis, it may be time to visit an academic medical center or, for pediatric patients, a children's hospital. Academic medical centers and children's hospitals, often called multidisciplinary care centers, typically bring together specialists from different fields to work together on complex cases like rare diseases.

Multidisciplinary care centers may offer more coordinated care and be involved in clinical research, which may help reduce the time to diagnosis and provide access to emerging diagnostic tools. Specialists at these centers may have a deeper understanding of rare diseases and serve as a resource when you'd like a second opinion, particularly when test results or treatment plans are not delivering expected results.

Find hospitals that may partner with medical schools and programs in your area. 

Children’s hospitals and large teaching hospitals may also offer dedicated specialists and programs for pediatric patients with undiagnosed or rare diseases. These programs bring pediatric experts together in one place and may provide more coordinated care for your child.

Search for children's or university hospitals in your area.


Rare Disease Experts

How can you find a rare disease expert?

If a diagnosis, care management, or treatment plan remains unclear despite extensive efforts by your PCP and specialists, it may be time to find a rare disease expert for your disease, if available. A rare disease expert is a medical provider that has knowledge or training on specific rare disease(s), but there may only be a few experts in your state, region, or country. Rare disease experts may work at large research or teaching hospitals, sometimes called centers of excellence. Centers of Excellence commit to sharing knowledge and best practices that can lead to improved care and treatment for individuals living with a rare disease. 

You can also contact a GARD Information Specialist for help finding experts, centers of excellence, or clinics that focus on your disease.

 

Find Your Community

How can patient organizations help?

Patient organizations can help patients and families connect. They build public awareness of the disease and are a driving force behind research to improve patients' lives. They may offer online and in-person resources to help people live well with their disease. Many collaborate with medical experts and researchers.

Services of patient organizations differ, but may include:

  • Ways to connect to others and share personal stories
  • Easy-to-read information
  • Up-to-date treatment and research information
  • Patient registries
  • Lists of specialists or specialty centers
  • Financial aid and travel resources


Please note: GARD provides organizations for informational purposes only and not as an endorsement of their services. Contact a GARD Information Specialist for more information on organizations that may be dedicated to this disease. Please contact an organization directly if you have questions about the information or resources it provides.


View GARD's criteria for including patient organizations, which can be found under the FAQs on our About GARD page. Request an update or to have your organization added to GARD

Patient Organizations

4 Organizations

People With

Rare Diseases

Country

United States

People With

Rare Diseases

Country

United States

People With

Rare Diseases

Country

United States

People With

Rare Diseases

Country

United States

Participate in Research

Clinical studies are a part of clinical research and play an important role in medical advances for rare diseases. Through clinical studies, researchers may ultimately uncover better ways to treat, prevent, diagnose, and understand human diseases.

What Are Clinical Studies?

Clinical studies are medical research involving people as participants. There are two main types of clinical studies:

  1. Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
  2. Observational studies involve recording changes over time among a specific group of people in their natural settings.

Learn more about clinical trials from this National Institutes of Health webpage.

Why Participate in Clinical Studies?

People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or a similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.

To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.

What if There Are No Available Clinical Studies?

Why may you want to consider joining the All of Us Research Program?

ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
Leave a detailed voice message and a GARD information specialist will respond to your inquiry.
Use the contact form to send your questions to a GARD Information Specialist.

Please allow 2 to 10 business days for us to respond.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Contact a GARD Information Specialist if you need help finding more information on this rare disease or available clinical studies. Please note that GARD cannot enroll individuals in clinical studies.
Leave a detailed voice message and a GARD information specialist will respond to your inquiry.
Use the contact form to send your questions to a GARD Information Specialist.

Please allow 2 to 10 business days for us to respond.

Last Updated: May 2026