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Participant 100

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.


Male, age 3, with global developmental delay, low muscle tone, and feeding difficulties

Interview (NBC DFW)

Date of Report

Dec 12, 2018


The participant had a complicated pregnancy and was delivered by C-section because he was in breech position. The delivery was difficult, and he had the umbilical cord wrapped around his neck at birth. He spent 16 days after delivery in the neonatal intensive care unit (NICU) and had trouble breathing and eating. He continued to have feeding difficulties as an infant and was put on a nasogastric (NG) tube until 6 months of age.

The participant continued to have trouble eating and developed vomiting and constipation issues. He is currently able to eat pureed foods, but not meats. He had surgery to place a G-tube at age 1.5 and, since then, his vomiting episodes have stopped. He also had surgery to release an upper lip tie and tongue tie, which improved his feeding. He had a small bowel biopsy that revealed abnormal thickness and orientation of the muscle layer consistent with myopathic pseudoobstruction.

Currently the participant is unable to walk or crawl and has no words. He did just learn his first sign and currently receives physical, occupational, and feeding therapy.  He had a muscle biopsy that showed non-specific finding of mild interstitial macrophage infiltration and very mild myopathic changes.

Symptoms / Signs
  • Global developmental delay
  • Delayed speech and language development
  • Low body weight for age
  • Feeding difficulties in infancy
  • Low muscle tone (generalized hypotonia)
  • Delayed bone age
  • Joint hypermobility
  • Long face
  • High forehead
  • Eye folds (epicanthus)
  • Far-sighted (hyperopia)
  • Limited tongue movement (ankyloglossia)
  • Upper lip tie
  • Genital abnormalities – undescended left testes (unilateral cryptorchidism) and micropenis
Current Treatments
  • G tube – feeding difficulties
  • Glasses – farsightedness
  • Physical, occupational, and feeding therapy
Prior Treatments
  • Milk of magnesia – constipation
  • NG tube – feeding difficulties
  • Testosterone – micropenis
Considered treatments
Previously Considered Diagnoses
  • Angelman syndrome
  • GLUT1 deficiency syndrome
  • Growth hormone deficiency
  • Microdeletion/duplication disorder
  • Mitochondrial disease
  • Myotonic dystrophy
  • Prader-Willi syndrome
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:

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

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


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