You are currently viewing Adams–Nance Syndrome :‎ Medical Notes & Mindmap

Adams-Nance Syndrome, also known as Nance-Horan Syndrome, is a rare genetic disorder characterized by facial abnormalities, mental retardation, and visual impairments. It is caused by mutations in the NDP gene, which is responsible for the production of a protein called nystagmus-associated protein.

Adams–Nance Syndrome :‎ [MEDNOTES+MINDMAP]


  • Adams–Nance Syndrome is a rare genetic disorder that affects the development and function of the nervous system.


  • The prevalence of Adams–Nance Syndrome is unknown, but it is thought to be rare.
  • Caused by mutations in the NALCN gene, which is inherited in an autosomal recessive pattern.

Natural history:

  • Symptoms typically appear in the first few months of life.
  • Affected individuals may have intellectual disability, developmental delays, and abnormal muscle tone.
  • They may also have problems with feeding, breathing, and movements.
  • The severity of the symptoms can vary widely among individuals 


  • Adams–Nance Syndrome can be classified based on the severity of the symptoms.
  • Some individuals may have mild symptoms while others may have severe symptoms.
  • The condition can also be classified based on the specific symptoms that are present.
  • For example, some individuals may have problems with feeding and breathing, while others may have more severe intellectual disability.
  • Risk Factors

    • Family history of Adams–Nance Syndrome
    • Mutation in the FBN1 gene
  • Etiology/Causes

    • Mutation in the FBN1 gene, which codes for the protein fibrillin-1
    • Fibrillin-1 is responsible for proper development and function of connective tissue in the body
  • Signs

    • Microcephaly (small head size)
    • Facial abnormalities (including wide-set eyes, small jaw, and narrow palate)
    • Skeletal abnormalities (including short stature, scoliosis, and joint contractures)
  • Symptoms

    • Intellectual disability
    • Developmental delays
    • Seizures
    • Vision problems
    • Heart defects
  • Pathology/Pathogenesis

    • The mutation in the FBN1 gene leads to abnormalities in the connective tissue, resulting in the physical and cognitive symptoms of Adams–Nance Syndrome.
    • These abnormalities can affect various systems in the body, including the skeletal, cardiovascular, and neurological systems.
  • Diagnosis/Laboratory Diagnosis:
    • Typically diagnosed in infancy or early childhood
    • Diagnosed through physical examination and genetic testing
  • Tests Required:
    • Genetic testing to confirm diagnosis
    • X-rays to assess bone abnormalities
    • CT/MRI scans to assess brain and facial abnormalities
  • Associated with/Strongly Associated with:
    • Mutation in the TNXB gene
    • Autosomal recessive inheritance pattern
  • Similar diseases/syndromes:
    • Ehlers-Danlos syndrome
    • Marfan syndrome
  • Treatment:
    • Physical therapy to address muscle and joint abnormalities
    • Orthopedic surgery for severe bone abnormalities
    • Speech therapy to address communication difficulties
    • Genetic counseling for family planning purposes

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