Novel Homozygous Variant Causing Late-onset Glycine Encephalopathy: A Case Report and Updated Review of the Literature

Overview

Journal Mol Genet Metab Rep

Specialty Endocrinology

Date 2023 Feb 23

PMID 36817643

Authors

Minh-Tuan Huynh

Emilie Landais

Jean-Madeleine de Sainte Agathe

Anne Panchout

De Vanssay De Blavous-Legendre Caroline

Henri Bruel

Affiliations

Soon will be listed here.

Abstract

Glycine encephalopathy (MIM #605899) is an autosomal recessive inborn error of metabolism caused by pathogenic variants in three genes , , encoding glycine cleavage enzyme system. We report an 8-year-old boy with late-onset glycine encephalopathy who harbors a novel homozygous likely pathogenic variant c.707G > A p.(Arg236Gln). Polyhydramnios was noted at fetal ultrasound. He displayed global developmental delay, craniofacial dysmorphism, convulsions. Our report expands the phenotypic and genetic spectrum of late-onset nonketotic hyperglycinemia.

Citing Articles

Natural history and outcome of nonketotic hyperglycinemia in China.

Zhou Z, Cai Y, Li X, Liu Z, Peng M, Lin Y Front Neurol. 2024; 15:1440883.

PMID: 39206282 PMC: 11351275. DOI: 10.3389/fneur.2024.1440883.

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