Novel compound heterozygous mutations of the DOCK6 gene in a familial case of Adams-Oliver syndrome 2

Gene. 2019 Jun 5:700:65-69. doi: 10.1016/j.gene.2019.03.023. Epub 2019 Mar 19.

Abstract

Introduction: Adams-Oliver syndrome (AOS) is a rare developmental disorder characterized by the combination of aplasia cutis congenita of the scalp vertex and terminal transverse limb defects. DOCK6 (Dedicator of cytokinesis 6) is one of the six identified AOS genes.

Methods: We performed targeted next-generation sequencing (NGS) of a child with an AOS phenotype. Sanger DNA sequencing further validated her lineal consanguinity. To explore the pathological features of the mutation, a minigene assay was used to investigate the effects of the mutation on splicing.

Results: Two compound heterozygous DOCK6 mutations (c.4106+2T>C and c.3063 C>G (p.Y1021*)) were identified in this family, and both mutations have not been reported previously. Sanger DNA sequencing indicated that the mutations were inherited maternally and paternally, respectively. The results of the minigene assay showed that the c.4106+2T>C mutation resulted in aberrant splicing and caused a four-nucleotide insertion in the transcript and a premature stop codon.

Conclusions: Our findings expanded the number of reported cases of this rare disease and the mutation spectrum of DOCK6 mutations, which can serve as the basis for prenatal diagnosis and genetic counseling.

Keywords: Adams-Oliver syndrome; DOCK6 gene mutation; Minigene assay; Next-generation sequencing.

MeSH terms

  • Child, Preschool
  • Consanguinity
  • Ectodermal Dysplasia / genetics*
  • Female
  • Genes, Recessive
  • Guanine Nucleotide Exchange Factors / genetics*
  • Heterozygote
  • Humans
  • Limb Deformities, Congenital / genetics*
  • Male
  • Mutation*
  • Pedigree
  • Phenotype
  • Scalp Dermatoses / congenital*
  • Scalp Dermatoses / genetics
  • Sequence Analysis, DNA / methods*

Substances

  • DOCK6 protein, human
  • Guanine Nucleotide Exchange Factors

Supplementary concepts

  • Adams Oliver syndrome