Identification of a pathogenic SMCHD1 variant in a Chinese patient with bosma arhinia microphthalmia syndrome: a case report

BMC Med Genomics. 2024 May 21;17(1):136. doi: 10.1186/s12920-024-01907-6.

Abstract

Background: Bosma arhinia microphthalmia syndrome (BAMS; MIM603457) is a rare genetic disorder, predominantly autosomal dominant. It is a multi-system developmental disorder characterized by severe hypoplasia of the nose and eyes, and reproductive system defects. BAMS is extremely rare in the world and no cases have been reported in Chinese population so far. Pathogenic variants in the SMCHD1 gene (MIM614982) cause BAMS, while the underlying molecular mechanisms requires further investigation.

Case presentation: In this study, a Chinese girl who has suffered from congenital absence of nose and microphthalmia was enrolled and subsequently submitted to a comprehensive clinical and genetic evaluation. Whole-exome sequencing (WES) was employed to identify the genetic entity of thisgirl. A heterozygous pathogenic variant, NM_015295, c.1025G > C; p. (Trp342Ser) of SMCHD1 was identified. By performing very detailed physical and genetic examinations, the patient was diagnosed as BAMS.

Conclusion: This report is the first description of a variant in SMCHD1 in a Chinese patient affected with BAMS.Our study not only furnished valuable genetic data for counseling of BAMS, but also confirmed the diagnosis of BAMS, which may help the management and prognosis for this patient.

Keywords: SMCHD1; Arhinia; Bosma arhinia microphthalmia syndrome; Whole-exome sequencing.

Publication types

  • Case Reports

MeSH terms

  • Asian People / genetics
  • China
  • Choanal Atresia* / genetics
  • Chromosomal Proteins, Non-Histone* / genetics
  • East Asian People
  • Exome Sequencing
  • Female
  • Humans
  • Microphthalmos* / genetics
  • Nose / abnormalities

Substances

  • SMCHD1 protein, human

Supplementary concepts

  • Arhinia, choanal atresia, and microphthalmia