First case of compound heterozygous BHLHA9 variants in mesoaxial synostotic syndactyly with phalangeal reduction

Am J Med Genet A. 2020 Apr;182(4):628-631. doi: 10.1002/ajmg.a.61480. Epub 2020 Jan 7.

Abstract

Mesoaxial synostotic syndactyly with phalangeal reduction (MSSD) is an extremely rare autosomal recessive limb abnormality characterized by the fusion of third and fourth fingers. To date, only homozygous missense and frameshift mutations have been reported in BHLHA9 associated to MSSD. In this study, we report a patient who presented with clinical and radiological features of MSSD. A customized skeletal dysplasia NGS panel revealed the presence of two novel compounds heterozygous variants in BHLHA9: NM_001164405.1: c.[226A>T][269G>C]; p.[(Lys76*)][(Arg90Pro)]. Thus, this is the first case of MSSD in a nonconsanguineous family.

Publication types

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

MeSH terms

  • Basic Helix-Loop-Helix Transcription Factors / genetics*
  • Female
  • Finger Phalanges / abnormalities*
  • Hand Deformities, Congenital / etiology
  • Hand Deformities, Congenital / pathology*
  • Heterozygote*
  • Humans
  • Infant, Newborn
  • Mutation, Missense*
  • Prognosis
  • Syndactyly / etiology
  • Syndactyly / pathology*
  • Synostosis / etiology
  • Synostosis / pathology*

Substances

  • BHLHA9 protein, human
  • Basic Helix-Loop-Helix Transcription Factors