|Signs and Symptoms||Approximate number of patients (when available)|
|Aplasia/Hypoplasia of the corpus callosum||50%|
|Hypoplasia of penis||50%|
|Abnormal renal physiology||7.5%|
|Abnormality of the sense of smell||7.5%|
|Aplasia/Hypoplasia of the cerebellum||7.5%|
|Sensorineural hearing impairment||7.5%|
|Absent septum pellucidum||-|
|Agenesis of corpus callosum||-|
|Anterior pituitary hypoplasia||-|
|Autosomal dominant inheritance||-|
|Autosomal recessive inheritance||-|
|Growth hormone deficiency||-|
|Optic disc hypoplasia||-|
|Optic nerve hypoplasia||-|
In most cases of septo-optic dysplasia, the cause of the disorder is unknown. Researchers suspect that a combination of genetic and environmental factors may play a role in causing this disorder. Proposed environmental risk factors include viral infections, specific medications, and a disruption in blood flow to certain areas of the brain during critical periods of development.
At least three genes have been associated with septo-optic dysplasia, although mutations in these genes appear to be rare causes of this disorder. The three genes, HESX1, OTX2, and SOX2, all play important roles in embryonic development. In particular, they are essential for the formation of the eyes, the pituitary gland, and structures at the front of the brain (the forebrain) such as the optic nerves. Mutations in any of these genes disrupt the early development of these structures, which leads to the major features of septo-optic dysplasia.
Researchers are looking for additional genetic changes that contribute to septo-optic dysplasia.
Septo-optic dysplasia is usually sporadic, which means that the condition typically occurs in people with no history of the disorder in their family.
Less commonly, septo-optic dysplasia has been found to run in families. Most familial cases appear to have an autosomal recessive pattern of inheritance, which means that both copies of an associated gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. In a few affected families, the disorder has had an autosomal dominant pattern of inheritance, which means one copy of an altered gene in each cell is sufficient to cause the condition.
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.
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.
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Are behavioral difficulties common among people with septo-optic dysplasia? See answer
I have septo-optic dysplasia. I have not had a sense of smell (anosmia) for as long as I can remember. Could this be connected to the septo-optic dysplasia? See answer
My nephew has been diagnosed with septo-optic dysplasia. My family is looking for information. Can this condition be cured? Are there any foundations that give support to families that are dealing with this illness. Are there any clinical studies being conducted for septo-optic dysplasia? See answer