De novo tandem duplication of chromosome segment 22q11-q12: clinical, cytogenetic, and molecular characterization.
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.
Lindsay
E A
EA
Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA.
Shaffer
L G
LG
Carrozzo
R
R
Greenberg
F
F
Baldini
A
A
D002869:Chromosome Aberrations / Q000235:genetics*; D025063:Chromosome Disorders; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D005260:Female; D006330:Heart Defects, Congenital / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007231:Infant, Newborn; D007621:Karyotyping; D013577:Syndrome