Expanding the phenotype of cerebellar-facial-dental syndrome: Two siblings with a novel variant in BRF1

Am J Med Genet A. 2020 Nov;182(11):2742-2745. doi: 10.1002/ajmg.a.61839. Epub 2020 Sep 8.

Abstract

Cerebellofaciodental syndrome (MIM #616202) is an autosomal recessive condition characterized by intellectual disability, microcephaly, cerebellar hypoplasia, dysmorphic features, and short stature. To date, eight patients carrying biallelic BRF1 variants have been reported. Here, we describe two siblings with congenital microcephaly and corpus callosum hypoplasia, pre and postnatal growth retardation, congenital heart defect and severe global developmental delay. We also detected additional findings not previously reported in this syndrome, including bilateral sensorineural hearing impairment and inner ear malformation. Whole exome sequencing identified a novel homozygous missense variant (c.654G>C, p.[Trp218Cys]) in BRF1, predicted to affect the protein structure. Expression assessment showed extremely low BRF1 protein expression caused by the identified variant, supporting its causal involvement. The description of new patients with cerebellofaciodental syndrome is essential to better delineate the phenotypic and genotypic spectrum of the disease.

Keywords: BRF1; cerebellofaciodental syndrome; growth retardation; microcephaly.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / genetics
  • Abnormalities, Multiple / pathology*
  • Cerebellum / abnormalities*
  • Cerebellum / pathology
  • Child
  • Craniofacial Abnormalities / genetics
  • Craniofacial Abnormalities / pathology*
  • Developmental Disabilities / genetics
  • Developmental Disabilities / pathology
  • Dwarfism / genetics
  • Dwarfism / pathology*
  • Exome Sequencing
  • Humans
  • Infant
  • Intellectual Disability / genetics
  • Intellectual Disability / pathology*
  • Male
  • Muscular Atrophy / genetics
  • Muscular Atrophy / pathology*
  • Mutation*
  • Nervous System Malformations / genetics
  • Nervous System Malformations / pathology*
  • Phenotype*
  • Siblings
  • TATA-Binding Protein Associated Factors / genetics*

Substances

  • BRF1 protein, human
  • TATA-Binding Protein Associated Factors

Supplementary concepts

  • Cerebellar Hypoplasia
  • Facial Dysmorphism with Multiple Malformations