NGLY1 deficiency-A rare congenital disorder of deglycosylation.

Abstract

Pathogenic variants in the NGLY1 gene are associated with a Congenital Disorder of Deglycosylation (CDDG) characterized by delays in reaching developmental milestones, complex hyperkinetic movement disorder, transient elevation of transaminases, and alacrima or hypolacrima. To date, only few cases of NGLY1 deficiency have been identified and reported in the literature. This report highlights a first child of non-consanguineous parents with no relevant family history who presented with hypotonia and poor weight gain since birth. At 2 months, the child developed paroxysmal cervical dystonia, posteriorly resolving spontaneously by age of 3. Subsequently, delays in reaching developmental milestones, ataxia, dyskinesia, visual impairment due to cone rod retinal dystrophy, low triglycerides, and persistently elevated liver transaminases were observed. Extensive etiological investigation was performed, including array-CGH and metabolic evaluation with no abnormalities to note. Trio whole exome analysis identified a homozygous pathogenic variant of the NGLY1 gene, c.1891del (p.Gln631Serfs*7), consistent with CDDG. Both parents were confirmed to be heterozygous carriers. The authors discuss in this case, the clinical presentation, the diagnostic challenges, and review other relevant NGLY1 deficiency cases previously reported in the literature. This case, along with the previous reported in the literature, indicates that pathogenic variants in NGLY1 cause a recognizable phenotype and should be considered in patients with a typical presentation. It also suggests that decreased sweating is not present universally in these patients.

• Authors: Patrícia Lipari Pinto, Catarina Machado, Patrícia Janeiro, Juliette Dupont, Sofia Quintas, Ana Berta Sousa, Ana Gaspar
• Journal: JIMD reports (JIMD Rep) Vol. 53 Issue 1 Pg. 2-9 (May 2020) ISSN: 2192-8304 [Print] United States
• PMID: 32395402 (Publication Type: Case Reports)
• Copyright: © 2020 The Authors. Journal of Inherited Metabolic Disease published by John Wiley & Sons Ltd on behalf of SSIEM.