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Disease at a Glance

Summary
Anterior segment developmental anomaly (ASD) refers to a spectrum of disorders that affect the development of the front of the eye (the anterior segment), which includes the cornea, iris, ciliary body, and lens. The specific eye abnormalities (alone or in combination) vary depending on the subtype of ASD and genetic cause, and some types may also be associated with neurological abnormalities. Glaucoma develops in approximately 60% of people with ASD, during infancy or much later. Specific eye signs and symptoms of ASD may include: Underdevelopment of the iris (iris hypoplasia). An enlarged or reduced cornea diameter. Growth of new blood vessels (vascularization) and opacity in the cornea. Posterior embryotoxon (a thickened and displaced Schwalbe's line). Corectopia (displacement of the pupil). Polycoria (more than one pupillary opening). An abnormal iridocorneal angle (the angle formed by the iris and cornea). Ectopia lentis (displacement of the lens). Aphakia (absent lens). Cataracts. Anterior synechiae (when the iris adheres to the cornea). Posterior keratoconus (thinning of the cornea). Individual disorders within the ASD spectrum include Axenfeld-Rieger syndrome (which includes disorders formerly known as Axenfeld anomaly, Axenfeld syndrome, Rieger anomaly, Rieger syndrome, and iridogoniodysgenesis) and Peters anomaly. ASD may be caused by genetic changes in any of several genes and inheritance can be autosomal dominant or autosomal recessive, depending on the responsible gene.
Summary
Anterior segment developmental anomaly (ASD) refers to a spectrum of disorders that affect the development of the front of the eye (the anterior segment), which includes the cornea, iris, ciliary body, and lens. The specific eye abnormalities (alone or in combination) vary depending on the subtype of ASD and genetic cause, and some types may also be associated with neurological abnormalities. Glaucoma develops in approximately 60% of people with ASD, during infancy or much later. Specific eye signs and symptoms of ASD may include: Underdevelopment of the iris (iris hypoplasia). An enlarged or reduced cornea diameter. Growth of new blood vessels (vascularization) and opacity in the cornea. Posterior embryotoxon (a thickened and displaced Schwalbe's line). Corectopia (displacement of the pupil). Polycoria (more than one pupillary opening). An abnormal iridocorneal angle (the angle formed by the iris and cornea). Ectopia lentis (displacement of the lens). Aphakia (absent lens). Cataracts. Anterior synechiae (when the iris adheres to the cornea). Posterior keratoconus (thinning of the cornea). Individual disorders within the ASD spectrum include Axenfeld-Rieger syndrome (which includes disorders formerly known as Axenfeld anomaly, Axenfeld syndrome, Rieger anomaly, Rieger syndrome, and iridogoniodysgenesis) and Peters anomaly. ASD may be caused by genetic changes in any of several genes and inheritance can be autosomal dominant or autosomal recessive, depending on the responsible gene.
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Resource(s) for Medical Professionals and Scientists on This Disease:

About Anterior segment developmental anomaly

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

  • Population Estimate:This section is currently indevelopment.
  • Symptoms:May start to appear as a Newborn.
  • Cause:This disease is caused by a change in the genetic material (DNA).
  • Organizations:Patient organizations are available to help find a specialist, or advocacy and support for this specific disease.
  • Categories:Birth DefectsGenetic Diseases
When Do Symptoms of Anterior segment developmental anomaly Begin?
Symptoms of this disease may start to appear as a Newborn.

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
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.

Symptoms

This section is currently in development. 

Causes

What Causes This Disease?

Genetic Mutations

Can This Disease Be Passed Down From Parent to Child?

Autosomal Dominant

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. 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 page.

Patient Organizations

5 Organizations

Organization Name

Who They Serve

Helpful Links

Country

People With

Anterior Segment Developmental Anomaly

Country

United States

People With

Rare Diseases

Helpful Links
Country

United States

People With

Rare Diseases

Helpful Links
Country

United States

People With

Rare Diseases

Helpful Links
Country

United States

People With

Rare Diseases

Helpful Links
Country

United States

Participating in Clinical Studies

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

What Are 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 U.S. Food & Drug Administration webpage.

Why Participate in Clinical Studies?

What if There Are No Available Clinical Studies?

Join the All of Us Research Program!

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 U.S. Food & Drug Administration webpage.
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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 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.
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What if There Are No Available Clinical Studies?

Join 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. 
Available toll-free Monday through Friday from 12 pm to 6 pm Eastern Time
(Except: Federal Holidays)
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. 
Available toll-free Monday through Friday from 12 pm to 6 pm Eastern Time
(Except: Federal Holidays)
Use the contact form to send your questions to a GARD Information Specialist.

Please allow 2 to 10 business days for us to respond.
Getting a Diagnosis

Take steps toward getting a diagnosis by working with your doctor, finding the right specialists, and coordinating medical care.

Last Updated: February 2024