Clinical Report: Warsaw Breakage Syndrome with small radii and fibulae

Am J Med Genet A. 2017 Nov;173(11):3075-3081. doi: 10.1002/ajmg.a.38382. Epub 2017 Sep 28.


We present two new cases of Warsaw Breakage Syndrome (WABS), an autosomal recessive cohesinopathy, in sisters aged 13 and 11 years who both had compound heterozygous mutations in DDX11. After exclusion of Fanconi anemia, Bloom syndrome and Nijmegen breakage syndrome, whole exome sequencing revealed two novel variants-c.1523T>G, predicting (p.Leu508Arg) and c.1949-1G>A (IVS19-1G>A), that were confirmed with Sanger sequencing in both affected individuals. DDX11 encodes an iron-sulfur-containing DNA helicase, and mutations in this gene have been reported in the five WABS cases previously identified to date. The sisters reported here display the distinguishing clinical features of WABS: pre- and post-natal growth restriction, microcephaly, intellectual disability, sensorineural hearing loss with cochlear abnormalities, and facial dysmorphic features. In addition, our cases had early menarche at 8 and 10 years of age, bilateral small thumbs, and the younger, more severely affected sister had small fibulae. These findings broaden the WABS phenotype and the limb malformations demonstrate further clinical overlap with Fanconi anemia and other cohesinopathies, such as Roberts Syndrome.

Keywords: DDX11; Warsaw Breakage Syndrome (WABS); chromosome breakage syndrome; cohesinopathy; genomic instability.

Publication types

  • Case Reports

MeSH terms

  • Abnormalities, Multiple / diagnosis
  • Abnormalities, Multiple / genetics
  • Abnormalities, Multiple / physiopathology
  • Adolescent
  • Child
  • Chromosome Breakage
  • DEAD-box RNA Helicases / genetics*
  • DNA Helicases / genetics*
  • Fanconi Anemia / diagnosis
  • Fanconi Anemia / genetics
  • Fanconi Anemia / physiopathology
  • Female
  • Genetic Predisposition to Disease
  • Gonadal Dysgenesis / diagnosis
  • Gonadal Dysgenesis / genetics*
  • Gonadal Dysgenesis / physiopathology
  • Hearing Loss, Sensorineural / diagnosis
  • Hearing Loss, Sensorineural / genetics*
  • Hearing Loss, Sensorineural / physiopathology
  • Humans
  • Intellectual Disability / diagnosis
  • Intellectual Disability / genetics*
  • Intellectual Disability / physiopathology
  • Mutation
  • Phenotype


  • DNA Helicases
  • DDX11 protein, human
  • DEAD-box RNA Helicases