Table 2.

Select Features of TSEN54 Pontocerebellar Hypoplasia Type 2

Feature% of Persons
with Feature
Severe developmental delay 100%
Neurologic Choreoathetosis88%62% w/pyramidal signs
Pure spasticity12%
Epileptic seizures82%
Dystonic attacks33%
Gastrointestinal Feeding difficulties100%
Sleep disorder 96%
Apnea 67%
Recurrent infections 52%

Based on 33 individuals homozygous for the common missense variant, p.Ala307Ser, from nonconsanguineous parents surviving until age 11 years [Sánchez-Albisua et al 2014]

GERD = gastroesophageal reflux disease

From: TSEN54 Pontocerebellar Hypoplasia

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