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A homozygous loss-of-function variant in BICD2 is associated with lissencephaly and cerebellar hypoplasia.

ABSTRACT: Developmental brain malformations are rare but are increasingly reported features of BICD2-related disorders. Here, we report a 2-year old boy with microcephaly, profound delay and partial seizures. His brain MRI showed lissencephaly, hypogenesis of corpus callosum, dysplastic hipocampus and cerebellar hypoplasia. Whole-exome sequencing identified a novel homozygous likely pathogenic variant in the BICD2 gene, c.229 C > T p.(Gln77Ter). This is the first report of lissencephaly and cerebellar hypoplasia seen in a patient with homozygous loss-of-function variant in BICD2 that recapitulated the animal model. Our report supports that BICD2 should be considered in the differential diagnosis for patients with lissencephaly and cerebellar hypoplasia Additional clinical features of BICD2 are likely to emerge with the identification of additional patients.

SUBMITTER: Abdel-Salam GMH

PROVIDER: S-EPMC9592554 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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A homozygous loss-of-function variant in BICD2 is associated with lissencephaly and cerebellar hypoplasia.

Abdel-Salam Ghada M H GMH Girgis Marian M Eid Maha M MM Sayed Inas S M ISM Abdel-Hamid Mohamed S MS

Journal of human genetics 20220727 11

Developmental brain malformations are rare but are increasingly reported features of BICD2-related disorders. Here, we report a 2-year old boy with microcephaly, profound delay and partial seizures. His brain MRI showed lissencephaly, hypogenesis of corpus callosum, dysplastic hipocampus and cerebellar hypoplasia. Whole-exome sequencing identified a novel homozygous likely pathogenic variant in the BICD2 gene, c.229 C > T p.(Gln77Ter). This is the first report of lissencephaly and cerebellar hyp ...[more]

PMID: 35896821

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