Proliferative vasculopathy and hydranencephaly-hydrocephaly syndrome or Fowler syndrome: Report of a family and insight into the disease's mechanism

Mol Genet Genomic Med. 2018 May;6(3):446-451. doi: 10.1002/mgg3.376. Epub 2018 Mar 3.

Abstract

Background: Fowler syndrome is a rare autosomal recessive disorder characterized by hydranencephaly-hydrocephaly and multiple pterygium due to fetal akinesia. To date, around 45 cases from 27 families have been reported, and the pathogenic bi-allelic mutations in FLVCR2 gene described in 15 families. The pathogenesis of this condition has not been fully elucidated so far.

Methods: We report on an additional family with two affected fetuses carrying a novel homozygous mutation in FLVCR2 gene, and describe the impact of known mutants on the protein structural and functional impairment.

Results: The present report confirms the genetic homogeneity of Fowler syndrome and describes a new FLVCR2 mutation affecting the protein function. The structural analysis of the present and previously published FLVCR2 mutations supports the hypothesis of a reduced heme import as the underlying disease's mechanism due to the stabilization of the occluded conformation or a protein misfolding.

Conclusion: Our data suggest the hypothesis of heme deficiency as the major pathogenic mechanism of Fowler syndrome.

Keywords: FLVCR2; Fowler syndrome; hydrocephaly; multiple pterygium.

Publication types

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

MeSH terms

  • Alleles
  • Amino Acid Sequence / genetics
  • Fetus / pathology
  • Heme / genetics
  • Heme / metabolism
  • Humans
  • Hydranencephaly / genetics*
  • Hydranencephaly / physiopathology
  • Hydrocephalus / genetics
  • Membrane Transport Proteins / genetics*
  • Membrane Transport Proteins / physiology
  • Mutation
  • Receptors, Virus / genetics*
  • Receptors, Virus / physiology
  • Vascular Diseases / genetics

Substances

  • FLVCR2 protein, human
  • Membrane Transport Proteins
  • Receptors, Virus
  • Heme

Supplementary concepts

  • Encephaloclastic Proliferative Vasculopathy