A Novel Homozygous Frameshift WDR81 Mutation associated with Microlissencephaly, Corpus Callosum Agenesis, and Pontocerebellar Hypoplasia

Abstract

Microlissencephaly is a brain malformation characterized by microcephaly and extremely simplified gyral pattern. It may be associated with corpus callosum agenesis and pontocerebellar hypoplasia. In this case report, we described two siblings, a boy and a girl, with this complex brain malformation and lack of any development. In the girl, exome sequencing of a gene set representing 4,813 genes revealed a homozygous AG deletion in exon 7 of the WDR81 gene, leading to a frameshift (c.4668_4669delAG, p.Gly1557AspfsTer16). The parents were heterozygous for this mutation. The boy died without proper genetic testing. Our findings expand the phenotypic and genotypic spectrum of WDR81 gene mutations.

Keywords

microlissencephaly - pontocerebellar hypoplasia - WDR81 mutation

Ethical Approval

Written informed parental consent had been obtained. The study was approved by the Human Investigation Review Board at Albert Szent-Györgyi Clinical Centre, University of Szeged, Hungary.

^* Tibor Kalmár and Katalin Szakszon contributed equally to this manuscript.

Publikationsverlauf

Eingereicht: 18. Februar 2020

Angenommen: 22. April 2020

Artikel online veröffentlicht:
28. Mai 2020

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