Congenital disorder of deglycosylation results from deficiencies in the NGLY1 gene. NGLY1 encodes the enzyme N-glycanase 1, which functions to removes glycosyl groups (sugars) from misfolded proteins. Deglycosylation of misfolded proteins is one of the first steps in their degradation and in the absence of NGLY1 function, these proteins accumulate and are thought to form aggregates that may damage cells. Patients display symptoms that include delayed speech and development of motor skills, movement abnormalities and seizures, liver issues, neurodegeneration of eye nerves and reductions in, or absence of, tears.
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