A previously unrecognized microdeletion syndrome on chromosome 22 Band q11.2 encompassing the BCR Gene

Academic Article

Abstract

  • Susceptibility of the chromosome 22q11.2 region to rearrangements has been recognized on the basis of common clinical disorders such as the DiGeorge/velocardiofacial syndrome (DG/VCFs). Recent evidence has implicated lowcopy repeats (LCRs); also known as segmental duplications; on 22q as mediators of nonallelic homologous recombination (NAHR) that result in rearrangements of 22q11.2. It has been shown that both deletion and duplication events can occur as a result of NAHR caused by unequal crossover of LCRs. Here we report on the clinical, cytogenetic and array CGH studies of a 15-year-old Hispanic boy with history of learning and behavior problems. We suggest that he represents a previously unrecognized microdeletion syndrome on chromosome 22 band q11.2 just telomeric to the DG/VCFs typically deleted region and encompassing the BCR gene. Using a 32K BAC array CGH chip we were able to refine and precisely narrow the breakpoints of this microdeletion, which was estimated to be 1.55-1.92 Mb in size and to span approximately 20 genes. This microdeletion region is flanked by LCR clusters containing several modules with a very high degree of sequence homology (>95%), and therefore could play a causal role in its origin. © 2007 Wiley-Liss, Inc.
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    Digital Object Identifier (doi)

    Author List

  • Mikhail FM; Descartes M; Piotrowski A; Andersson R; de Ståhl TD; Komorowski J; Bruder CEG; Dumanski JP; Carroll AJ
  • Start Page

  • 2178
  • End Page

  • 2184
  • Volume

  • 143
  • Issue

  • 18