NGLY1 Deficiency: A Prospective Natural History Study

Study Summary

NGLY1 deficiency is a rare genetic disorder that is characterized by: global developmental delay and/or intellectual disability, hypo- or alacrima, transient elevation of transaminases, and a hyperkinetic movement disorder. Significant phenotypic variability has been observed in the small number of affected individuals described in the medical literature. The purpose of this study is to describe the natural history of NGLY1 deficiency in a prospective, detailed, and highly uniform manner. Study participants will be closely monitored over the course of five years in order to: * understand the clinical spectrum and progression of NGLY1 deficiency using standardized clinical and neurodevelopmental assessments * identify clinical and biomarker endpoints for use in therapeutic trials, and * identify genotype-phenotype correlations Close clinical follow-up will allow for generation of a rich dataset and detailed understanding of the natural history of NGLY1 deficiency.

Primary Outcome

Conducted in patients with NGLY1 deficiency: detailed standardized general, neurologic, dysmorphologic, and ophthalmologic evaluations; clinical laboratory studies; electroencephalogram; nerve conduction studies; quantitative studies of autonomic function; scoring of movement disorder and NGLY1 deficiency symptom scales; and a timed 10-meter walk test. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neurops

Interventions

• OTHER Neurodevelopmental Assessment