5q14.3 microdeletion syndrome

Alternate names

Chromosome 5q14.3 deletion syndrome; Monosomy 5q14.3; Del(5)(q14.3); 5q14.3 deletion syndrome; Autosomal dominant intellectual disability 20

Definition

5q14.3 microdeletion syndrome is characterized by severe intellectual disability, absent speech, stereotypic movements and epilepsy.

Cause

The condition is caused by mutations affecting the MEF2C gene and deletions in the q14.3 region of chromosome 5.

Signs and symptoms

• It is characterized by severe intellectual disability, absent speech, stereotypic movements and epilepsy.
• Unusual facial features include high broad forehead with variable small chin, short nose with anteverted nares (nostrils that open to the front rather than downward), large open mouth, upslanted palpebral fissures (outside corners of the eyes that point downward), and prominent eyebrows.

Clinical presentation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 80%-99% of people have these symptoms

• Autistic behavior
• Broad forehead(Increased width of the forehead)
• Delayed speech and language development(Deficiency of speech development)
• High forehead
• Intellectual disability, severe(Early and severe mental retardation)
• Muscular hypotonia(Low or weak muscle tone)
• Seizure

30%-79% of people have these symptoms

• Hypoplasia of the corpus callosum(Underdevelopment of part of brain called corpus callosum)
• Short nose(Decreased length of nose)
• Short philtrum
• Stereotypy(Repetitive movements)
• Upslanted palpebral fissure(Upward slanting of the opening between the eyelids)
• Ventriculomegaly

5%-29% of people have these symptoms

• Abnormality of the periventricular white matter
• Agenesis of cerebellar vermis
• Anteverted nares(Nasal tip, upturned)
• Deeply set eye(Deep set eye)
• Epileptic encephalopathy
• Feeding difficulties(Feeding problems)
• Frontal cortical atrophy
• Open mouth(Gaped jawed appearance)
• Optic nerve hypoplasia
• Strabismus(Cross-eyed)
• Thick eyebrow(Bushy eyebrows)
• Toe syndactyly(Fused toes)

NIH genetic and rare disease info

• NIH info on 5q14.3 microdeletion syndrome

5q14.3 microdeletion syndrome is a rare disease.

Resources

Frequently asked questions

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