You are currently viewing Acrocallosal Syndrome :‎ Medical Notes & Mindmap

Acrocallosal syndrome is a rare genetic disorder that is characterized by abnormal development of the brain and skull. It is a congenital condition, which means it is present at birth.

Affected individuals typically have a small head (microcephaly), a split in the corpus callosum (the structure that connects the two hemispheres of the brain), and abnormalities in the bones of the skull and face

Acrocallosal Syndrome :‎ [MEDNOTES+MINDMAP]


  • Rare genetic disorder caused by a mutation in the ARFGEF2 gene
  • Characterized by abnormal development of the brain and skull, as well as physical and cognitive abnormalities


  • Occurs in approximately 1 in 500,000 live births
  • More common in males
  • Can occur in all ethnicities

Natural history:

  • Onset of symptoms at birth or within the first few months of life
  • Symptoms may vary in severity and progression
  • Life expectancy may be shortened due to complications related to the syndrome


  • Acrocallosal syndrome can be classified into 3 types based on the severity of symptoms:
    • Type 1: mildest form with less severe brain abnormalities and better overall prognosis
    • Type 2: moderate form with more severe brain abnormalities and a poorer prognosis
    • Type 3: severe form with severe brain abnormalities and the poorest prognosis
  • There are also stages of the syndrome based on physical and cognitive development:
    • Stage 1: Infancy (0-12 months)
    • Stage 2: Early childhood (1-5 years)
    • Stage 3: Late childhood (6-12 years)
    • Stage 4: Adolescence (13-18 years)
    • Stage 5: Adulthood (19+ years)
  • Risk Factors:

    • Mutation in the GLI3 gene
    • Parental consanguinity (close blood relationship between parents)
    • Environmental factors during pregnancy (such as exposure to certain chemicals)
  • Etiology/Causes:

    • Genetic mutations, specifically in the GLI3 gene
    • Environmental factors during pregnancy
  • Signs:

    • Absence or underdevelopment of the corpus callosum (a structure in the brain that connects the left and right hemispheres)
    • Abnormalities in the shape and size of the head and face
    • Underdeveloped or missing fingers and toes
    • Spinal abnormalities
    • Delay in physical and intellectual development
  • Symptoms:

    • Intellectual disability
    • Delays in reaching developmental milestones
    • Seizures
    • Abnormal reflexes
    • Vision and hearing problems
    • Abnormal movements
  • Pathology/Pathogenesis:

    • Mutations in the GLI3 gene lead to abnormal development of the central nervous system during pregnancy, resulting in the various physical and intellectual abnormalities seen in individuals with Acrocallosal Syndrome.
    • This can be caused by both genetic and environmental factors.
  • Diagnosis/Laboratory Diagnosis:
    • Symptoms may include abnormal brain development, abnormal facial features, missing or shortened fingers and toes, and developmental delays
    • Genetic testing may be conducted to confirm diagnosis
    • MRI or CT scans may be used to assess brain and skull development
    • Chromosomal analysis may also be conducted to identify any chromosomal abnormalities
  • Tests Required:
    • Genetic testing
    • MRI or CT scans
    • Chromosomal analysis
  • Associated with:
    • Chromosomal abnormalities, specifically deletion or mutation of the ACR locus on chromosome 7
    • Maternal diabetes and advanced maternal age may also increase the risk of Acrocallosal Syndrome
  • Similar diseases/syndromes:
    • Aarskog-Scott Syndrome
    • Dandy-Walker Syndrome
    • Meckel-Gruber Syndrome Treatment:
    • Treatment may include physical therapy, speech therapy, and occupational therapy to address developmental delays and physical abnormalities
    • Medications may be prescribed to manage seizures or other medical issues
    • Surgery may be necessary to address physical abnormalities such as missing fingers or toes
    • Supportive care and rehabilitation services may be necessary to improve quality of life and manage daily living tasks.

Dr. Arin Nandi

Passionate About Medical Science & Helping Future Doctors Achieve Top Ranks In Medical Exams. He is professionally a dentist as well as a public health expert from JIPMER working in department