background participants

Participant 045

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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 4, with developmental delay, difficulty coordinating voluntary muscle movements (ataxia), autistic behaviors, and different facial features

Date of Report

Jan 08, 2018


At 10 months of age, the participant was found to have low muscle tone (hypotonia) and developmental delay. He said his first words at 9 months and has added vocabulary slowly over the years. According to his speech therapist, he has a diagnosis of dysarthria. He began walking at 28 months, but developed a wide and abnormal walk (broad-based gait, gait ataxia). He now walks independently, but becomes tired after about 40 steps (increased muscle fatigability). He has difficulty with coordination and falls frequently (ataxia). However, he is able to eat independently and can follow two step commands.

The participant also has dark birthmarks on his forearms, face, and neck (mosaic hyperpigmented nevi) and light colored birthmarks on his hands and back (café au lait spots). Some of his other symptoms include: middle ear abnormalities (middle ear effusions, recurrent otitis media), and autism spectrum disorder.

Symptoms / Signs
  • Global developmental delay
  • Difficulty controlling voluntary movements (ataxia)
  • Wide-based walking (broad-based gait)
  • Uncoordinated walking (gait ataxia)
  • Fear of loud sounds (phonophobia)
  • Repetitive behavior (stereotypic behavior)
  • Autistic behavior
  • Increased muscle fatigability
  • Low muscle tone (muscular hypotonia)
  • Brain abnormalities (progressive cerebellar ataxia, mild diffuse cerebral atrophy, brainstem dysplasia, hypoplasia of ventral pons, ill-defined olivary nuclei)
  • Abnormal facial shape (frontal bossing, high anterior hairline, prominent glabella)
  • Smooth area between nose and upper lip (smooth philtrum)
  • Downturned corners of mouth
  • Dysarthria
  • Wide nasal bridge
  • Vertical fold of skin covering inner eye (epicanthus)
  • Cupped ear
  • Low-set ears turned towards back of the head (low-set, posteriorly rotated ears)
  • Recurrent middle ear infections (recurrent otitis media)
  • Abnormality of the middle ear (middle ear effusions)
  • Widely spaced nipples (wide intermamillary distance)
  • Curved ring and pinky finger (clinodactyly of the 4th and 5th finger)
  • Bilateral tapered fingers
  • Dark pigmented birthmarks on forearms, face and neck (mosaic hyperpigmented nevi)
  • Light colored birthmarks on back of right hand, left hand, and upper back (café au lait spots)
  • Curved right lower leg (right tibial bowing)
  • Outward turning of heel (talipes valgus)
Current Treatments
Prior Treatments
Considered treatments
Previously Considered Diagnoses
  • Angelman syndrome
  • Fragile X syndrome
  • Glycogen storage disorder
  • Isobutyryl-CoA dehydrogenase deficiency
  • MECP2-related condition
  • Metabolic condition
  • Mitochondrial condition
  • Prader-Willi syndrome
  • Spinocerebellar ataxia
  • Wolf Hirschhorn syndrome
Other Photographs
Genetic Variants of Interest

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


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