A De Novo FOXP1 Truncating Mutation in a Patient Originally Diagnosed as C Syndrome

Sci Rep. 2018 Jan 12;8(1):694. doi: 10.1038/s41598-017-19109-9.

Abstract

De novo FOXP1 mutations have been associated with intellectual disability (ID), motor delay, autistic features and a wide spectrum of speech difficulties. C syndrome (Opitz C trigonocephaly syndrome) is a rare and genetically heterogeneous condition, characterized by trigonocephaly, craniofacial anomalies and ID. Several different chromosome deletions and and point mutations in distinct genes have been associated with the disease in patients originally diagnosed as Opitz C. By whole exome sequencing we identified a de novo splicing mutation in FOXP1 in a patient, initially diagnosed as C syndrome, who suffers from syndromic intellectual disability with trigonocephaly. The mutation (c.1428 + 1 G > A) promotes the skipping of exon 16, a frameshift and a premature STOP codon (p.Ala450GLyfs*13), as assessed by a minigene strategy. The patient reported here shares speech difficulties, intellectual disability and autistic features with other FOXP1 syndrome patients, and thus the diagnosis for this patient should be changed. Finally, since trigonocephaly has not been previously reported in FOXP1 syndrome, it remains to be proved whether it may be associated with the FOXP1 mutation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autistic Disorder / complications
  • Autistic Disorder / diagnosis
  • Craniosynostoses / diagnosis*
  • Craniosynostoses / genetics
  • Exome Sequencing
  • Exons
  • Forkhead Transcription Factors / genetics*
  • Frameshift Mutation
  • Humans
  • Intellectual Disability / diagnosis*
  • Intellectual Disability / genetics
  • Male
  • RNA Splicing
  • Repressor Proteins / genetics*
  • Speech Disorders / complications
  • Speech Disorders / diagnosis
  • Young Adult

Substances

  • FOXP1 protein, human
  • Forkhead Transcription Factors
  • Repressor Proteins

Supplementary concepts

  • Opitz trigonocephaly syndrome