De novo tandem duplication of chromosome segment 22q11-q12: clinical, cytogenetic, and molecular characterization

Am J Med Genet. 1995 Apr 10;56(3):296-9. doi: 10.1002/ajmg.1320560316.


We report on a case of duplication of the segment 22q11-q12 due to a de novo duplication. Molecular cytogenetics studies demonstrated this to be a tandem duplication, flanked proximally by the marker D22Z4, a centromeric alpha satellite DNA repeat, and distally by D22S260, an anonymous DNA marker proximal to the Ewing sarcoma breakpoint. The segment includes the regions responsible for the "cat-eye," Di George, and velo-cardio-facial syndromes and extends distal to the breakpoint cluster region (BCR). The clinical picture is dominated by the cardiac defects and includes findings reminiscent of "cat-eye" syndrome. These findings reinforce the hypothesis that the proximal 22q region contains dosage-sensitive genes involved in development.

Publication types

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

MeSH terms

  • Chromosome Aberrations / genetics*
  • Chromosome Disorders
  • Chromosomes, Human, Pair 22 / genetics*
  • Female
  • Heart Defects, Congenital / genetics
  • Humans
  • In Situ Hybridization, Fluorescence
  • Infant, Newborn
  • Karyotyping
  • Syndrome