background participants

Participant 123

On this page, you will find information about a UDN participant.

Sharing information on this website is not a requirement of UDN participation. Only descriptions about participants who give explicit consent will appear here. While these participant pages are helpful to understand our participants’ stories, they do not begin to describe their diagnostic odysseys. A special thank you goes out to our participants and their families for sharing their experiences.


Female, age 2 with global developmental delay, brain abnormalities, abnormal head movements, and trembling during precise movement (intention tremor)

Date of Report

Apr 18, 2019


At 3 months, the participant’s parents noticed that she was not yet rolling over. Around 4.5 months, she started vomiting every two or three days. Soon after, she was noticed to have frequent and unusual head movements. During these episodes, she would move her head from side to side and her eyes would roll up. She was diagnosed with significant low muscle tone (hypotonia), no head control, mildly increased reflexes, and intermittent head shaking/tremor. She underwent an electroencephalogram (EEG), which was normal. A brain MRI showed enlargement of the subarachnoid spaces. A follow-up brain MRI showed other abnormal findings (abnormal cerebellum morphology, cerebellar atrophy, cerebellar vermis atrophy, open operculum).

Currently the participant still has unusual head movements, but they are less frequent. She has some shakiness when she is falling asleep, waking up, or reaching for objects. She also had a gastrostomy tube (G-tube) placed because of her vomiting episodes.

Symptoms / Signs
  • Global developmental delay
  • Brain abnormalities (abnormal cerebellum morphology, cerebellar atrophy, cerebellar vermis atrophy, open operculum)
  • Abnormal head movements
  • Trembling during precise movement (intention tremor)
  • Low muscle tone (generalized hypotonia)
  • Failure to thrive in infancy
  • Large head size (relative macrocephaly)
  • Poor head control
  • Broad forehead
  • Eye fold (epicanthus)
  • Repetitive, uncontrolled eye movements (nystagmus)
  • Farsighted (hypermetropia)
  • Left eye turned inward (esotropia)
  • Tooth abnormalities (delayed eruption and hypoplasia of primary teeth)
  • Obstructive sleep apnea
  • Chronic constipation
Current Treatments
  • Manganese supplement
  • Multivitamin with zinc
Prior Treatments
  • G-tube- vomiting episodes
Considered treatments
Previously Considered Diagnoses
  • Angelman syndrome
  • Congenital disorder of glycosylation
  • Lysosomal storage disorder
  • Metabolic condition
  • Microdeletion/duplication disorder
  • Mitochondrial condition
  • Neuromuscular condition
  • Single gene disorder
Other Photographs
Genetic Variants of Interest

Clinicians and researchers are investigating the following genetic change to see if it is causing the participant’s symptoms:

*Note: only one variant identified.

Inheritance Pattern
Position (hg19)
DNA Change
Protein Change
Autosomal recessive

If this participant sounds like you or someone you know, please contact us!


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