Mental retardation and microcephaly with pontine and cerebellar hypoplasia

Rare genetic disorder

Mental retardation and microcephaly with pontine and cerebellar hypoplasia (MICPCH) is a rare genetic disorder characterized by intellectual disability, microcephaly, and underdevelopment of the pons and cerebellum in the brain. This condition is associated with mutations in the CASK gene, which is located on the X chromosome.

Presentation

X-linked dominant inheritance pattern

Individuals with MICPCH typically present with severe intellectual disability and developmental delay. Microcephaly, a condition where the head circumference is significantly smaller than average for the person's age and sex, is a hallmark feature. The pons and cerebellum, parts of the brain responsible for motor control and coordination, are underdeveloped, leading to hypotonia (reduced muscle tone) and ataxia (lack of voluntary coordination of muscle movements).

Genetics

MICPCH is caused by mutations in the CASK gene, which encodes a protein involved in synaptic transmission and neurodevelopment. The disorder follows an X-linked dominant inheritance pattern, meaning that a single copy of the mutated gene on one of the X chromosomes can cause the disorder. This pattern of inheritance is more commonly observed in females, as males with the mutation often do not survive to birth.

Diagnosis

Diagnosis of MICPCH is based on clinical features, neuroimaging, and genetic testing. Magnetic resonance imaging (MRI) of the brain typically reveals pontine and cerebellar hypoplasia. Genetic testing can confirm mutations in the CASK gene.

Management

There is currently no cure for MICPCH, and treatment is supportive and symptomatic. Management may include physical therapy, occupational therapy, and speech therapy to address developmental delays and improve quality of life. Regular monitoring by a multidisciplinary team is essential to address the various medical and developmental needs of affected individuals.

Prognosis

The prognosis for individuals with MICPCH varies depending on the severity of the condition. Most individuals have significant developmental challenges and require lifelong care. Life expectancy may be reduced, particularly in males who are more severely affected.

Related pages

• Intellectual disability
• Microcephaly
• Cerebellar hypoplasia
• X-linked dominant inheritance