Rare Endocrinology News

Disease Profile

Syndromic microphthalmia-12

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Microphthalmia with or without pulmonary hypoplasia, diaphragmatic hernia, and/or cardiac defects


Syndromic microphthalmia-12 is a genetic syndrome with the main features of small eyeballs (microphthalmia), lungs that are too small (pulmonary hypoplasia), and a defect or hole in the diaphragm that allows the abdominal contents to move into the chest cavity (diaphragmatic hernia).[1] People with this syndrome also have progressive movement disorders that cause severe global developmental delay. These movement disorders include spasticity and/or dystonia, with or without abnormal quick movements that resemble dancing (chorea). Within the brain, there can be defects of the cerebellum (Chiari type I malformation) and a build up of cerebrospinal fluid (hydrocephaly). This syndrome causes severe feeding problems and language delay. Facial features seen in people with this syndrome include a broad nose, and a very small chin (micrognathia). Syndromic microphthalmia-12 is caused by mutations in the RARB gene. Treatment for this syndrome is based on addressing any symptoms that a person experiences.[1][2][3]


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.

Organizations Supporting this Disease


  1. Microphthalmia, syndromic 12. OMIM. 2017; https://omim.org/entry/615524.
  2. Srour M & cols. Gain-of-Function Mutations in RARB Cause Intellectual Disability with Progressive Motor Impairment. Hum Mutat. August, 2016:; 37(8):786-93. https://www.ncbi.nlm.nih.gov/pubmed/?term=27120018.
  3. Srour M & cols. Recessive and Dominant Mutations in Retinoic Acid Receptor Beta in Cases with Microphthalmia and Diaphragmatic Hernia. American Journal of Human Genetics. 2013; 93(4):765-772. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3791254/.