A case of YY1-associated syndromic learning disability or Gabriele-de Vries syndrome with myasthenia gravis

Am J Med Genet A. 2018 Dec;176(12):2846-2849. doi: 10.1002/ajmg.a.40626. Epub 2018 Dec 14.


Exome sequencing is being used increasingly to evaluate patients with intellectual disability. YY1 is a ubiquitously distributed transcription factor belonging to the GLIKruppel class of zinc finger proteins recently recognized as the causative gene in 23 patients for the Gabriele-de Vries syndrome. We report a new case with similar features and a novel variant in YY1, in a region of the gene, which has not previously been reported. A 25 year old female was referred to clinical genetics with a diagnosis of autoimmune myasthenia gravis, facial dysmorphism and learning disability. Chromosomal microarray and gene panel test for congenital myasthenic syndrome was negative. Whole exome sequencing (WES) revealed a presumed pathogenic de novo novel, heterozygous, truncating variant in the YY1 gene, c.860_864delTTAAAA, p.Ile287Argfs*3. The Ile287 residue is conserved across species and is situated in the transcription repressor domain of the protein. This variant is novel and lies in a domain of the protein where no previously reported variants occur. The phenotypic features of our case closely match those of the reported patients. Autoimmune myasthenia gravis has not been reported in these patients and may constitute an expansion of this phenotypic spectrum or perhaps more likely a second unrelated diagnosis.

Keywords: YY1; Gabriele-de Vries; learning disability; myasthenia gravis; yin and Yang 1.

Publication types

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

MeSH terms

  • Adult
  • Biomarkers
  • Chromosome Aberrations
  • Exome Sequencing
  • Facies
  • Female
  • Genetic Association Studies*
  • Heterozygote
  • Humans
  • Learning Disabilities / diagnosis*
  • Learning Disabilities / genetics*
  • Myasthenia Gravis / complications*
  • Myasthenia Gravis / diagnosis
  • Phenotype
  • Radiography, Thoracic
  • Syndrome
  • Tomography, X-Ray Computed
  • YY1 Transcription Factor / genetics*


  • Biomarkers
  • YY1 Transcription Factor
  • YY1 protein, human

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