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Novel homozygous GLDC variant causing late-onset glycine encephalopathy: A case report and updated review of the literature.

ABSTRACT: Glycine encephalopathy (MIM #605899) is an autosomal recessive inborn error of metabolism caused by pathogenic variants in three genes GLDC, AMT, GCSH encoding glycine cleavage enzyme system. We report an 8-year-old boy with late-onset glycine encephalopathy who harbors a novel homozygous GLDC 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.

SUBMITTER: Huynh MT

PROVIDER: S-EPMC9932748 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Novel homozygous GLDC variant causing late-onset glycine encephalopathy: A case report and updated review of the literature.

Huynh Minh-Tuan MT Landais Emilie E Agathe Jean-Madeleine De Sainte JS Panchout Anne A Caroline De Vanssay De Blavous-Legendre VB Bruel Henri H

Molecular genetics and metabolism reports 20230206

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

PMID: 36817643

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