What are the other Names for this Condition? (Also known as/Synonyms)

• X-Linked Intellectual Disability, Corpus Callosum Agenesis, Spastic Quadriparesis Syndrome

What is X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome? (Definition/Background Information)

• X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome is characterized by intellectual and motor deficit, spastic quadriparesis and agenesis of the corpus callosum, without craniofacial abnormalities or seizures
• The disorder has been described in four male members of a family. The mode of inheritance is most likely X-linked recessive

(Source: X-linked intellectual disability-corpus callosum agenesis-spastic quadriparesis syndrome; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Who gets X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome? (Age and Sex Distribution)

• X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome is an extremely rare congenital disorder. So far, the syndrome has been reported in 4 male members of a single family
• The presentation of symptoms may occur at birth or in infancy
• The disorder predominantly affects males
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome? (Predisposing Factors)

• A positive family history may be an important risk factor, since X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome can be inherited
• Currently, no other risk factors have been clearly identified for the syndrome

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome? (Etiology)

• X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome is caused by mutation(s) in X chromosome, although the exact genetic mutation that leads to the condition is not known
• The disorder is believed to be transmitted in an X-linked recessive manner

X-linked recessive pattern of inheritance: The gene associated with this condition is believed to be located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

What are the Signs and Symptoms of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome?

The signs and symptoms of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome may vary among affected individuals in type and severity. They may include the following:

• Agenesis of corpus callosum
• Global developmental delay
• Intellectual disability
• Spastic tetraparesis

(Source: X-linked intellectual disability-corpus callosum agenesis-spastic quadriparesis; Genetic and Rare Disease Information Center (GARD) of National Center for Advancing Translational Science (NCATS), USA.)

How is X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome Diagnosed?

X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough medical history evaluation
• Assessment of signs and symptoms
• Laboratory tests
• Imaging studies
• Biopsy studies, if necessary

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome?

The complications of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome may include:

• Extreme muscle weakness, leading to problems with movement
• Risk of falls due to clumsiness
• Severe intellectual disability

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome Treated?

There is no cure for X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome, since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complication that develop.

How can X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome be Prevented?

X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome may not be preventable, since it is a genetic disorder.

• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders
• Regular medical screening at periodic intervals with tests and physical examinations are recommended

What is the Prognosis of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome? (Outcomes/Resolutions)

• The prognosis of X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for X-Linked Intellectual Disability-Corpus Callosum Agenesis-Spastic Quadriparesis Syndrome:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/