Understanding the phenotypic spectrum of ASXL-related disease: Ten cases and a review of the literature

Am J Med Genet A. 2021 Jun;185(6):1700-1711. doi: 10.1002/ajmg.a.62156. Epub 2021 Mar 10.

Abstract

Over the past decade, pathogenic variants in all members of the ASXL family of genes, ASXL1, ASXL2, and ASXL3, have been found to lead to clinically distinct but overlapping syndromes. Bohring-Opitz syndrome (BOPS) was first described as a clinical syndrome and later found to be associated with pathogenic variants in ASXL1. This syndrome is characterized by developmental delay, microcephaly, characteristic facies, hypotonia, and feeding difficulties. Subsequently, pathogenic variants in ASXL2 were found to lead to Shashi-Pena syndrome (SHAPNS) and in ASXL3 to lead to Bainbridge-Ropers syndrome (BRPS). While SHAPNS and BRPS share many core features with BOPS, there also seem to be emerging clear differences. Here, we present five cases of BOPS, one case of SHAPNS, and four cases of BRPS. By adding our cohort to the limited number of previously published patients, we review the overlapping features of ASXL-related diseases that bind them together, while focusing on the characteristics that make each neurodevelopmental syndrome unique. This will assist in diagnosis of these overlapping conditions and allow clinicians to more comprehensively counsel affected families.

Keywords: ASXL1; ASXL2; ASXL3; Bainbridge-Ropers syndrome; Bohring-Opitz syndrome; Shashi-Pena syndrome.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Craniosynostoses / genetics*
  • Craniosynostoses / pathology
  • Developmental Disabilities / epidemiology
  • Developmental Disabilities / genetics*
  • Developmental Disabilities / pathology
  • Female
  • Genetic Predisposition to Disease
  • Humans
  • Infant
  • Intellectual Disability / genetics*
  • Intellectual Disability / pathology
  • Male
  • Microcephaly
  • Muscle Hypotonia / epidemiology
  • Muscle Hypotonia / genetics
  • Muscle Hypotonia / pathology
  • Mutation
  • Phenotype
  • Repressor Proteins / genetics*
  • Transcription Factors / genetics*
  • Young Adult

Substances

  • ASXL1 protein, human
  • ASXL2 protein, human
  • ASXL3 protein, human
  • Repressor Proteins
  • Transcription Factors

Supplementary concepts

  • Bohring syndrome