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Biallelic Variants in LAMB1 Causing Hydranencephaly: A Severe Phenotype of a Rare Malformative Encephalopathy.

ABSTRACT: Case Report ?A 32-year-old female with a history of three prior pregnancy losses presented for genetic testing following an ultrasonography diagnosis of fetal hydranencephaly. Baby was born via C-section and was noted to have a head circumference of 48?cm, in addition to ocular and cardiac anomalies and dysmorphic features. Whole genome sequencing revealed a homozygous variant in LAMB1 gene. Discussion ?The pathobiogenesis of hydranencephaly is incompletely understood and is attributed to vascular, infectious, or genetic etiology. Herein we present LAMB1 as a monogenic cause of fetal hydranencephaly which was incompatible with life. Previously, LAMB1 -associated phenotype consisted of cobblestone lissencephaly and hydrocephalus, developmental delay, and seizures. Our proband expands the phenotypic spectrum of this malformative encephalopathy.

SUBMITTER: Sen K

PROVIDER: S-EPMC7850915 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Biallelic Variants in LAMB1 Causing Hydranencephaly: A Severe Phenotype of a Rare Malformative Encephalopathy.

Sen Kuntal K Kaur Shagun S Stockton David W DW Nyhuis Mary M Roberson Jacquelyn J

AJP reports 20210101 1

Case Report A 32-year-old female with a history of three prior pregnancy losses presented for genetic testing following an ultrasonography diagnosis of fetal hydranencephaly. Baby was born via C-section and was noted to have a head circumference of 48 cm, in addition to ocular and cardiac anomalies and dysmorphic features. Whole genome sequencing revealed a homozygous variant in LAMB1 gene. Discussion The pathobiogenesis of hydranencephaly is incompletely understood and is ...[more]

PMID: 33542858

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