title: Co-existence of other copy number variations with 22q11.2 deletion or duplication: a modifier for variable phenotypes of the syndrome?
abstract: BACKGROUND
  The phenotype in patients with a 22q11.2 deletion or duplication can be extremely variable, and the causes of such as variations are not well known.
  
  
  RESULTS
  We observed additional copy number variations (CNVs) in 2 of 15 cases with a 22q11.2 deletion or duplication. Both cases were newborn babies referred for severe congenital heart defects. The first case had a deletion with a size of approximately 1.56 Mb involving multiple genes including STS in the Xp22.31 region along with a 22q11.2 deletion. The second case had a duplication of 605 kb in the 15q13.3 region encompassing CHRNA7 and a deletion of 209 kb involving the RBFOX1 gene in the 16p13.2 region, in addition to 22q11.2 duplication.
  
  
  CONCLUSIONS
  Our observations have shown that additional CNVs are not rare (2/15, 13%) in patients with a 22q11.2 deletion or duplication. We speculate that these CNVs may contribute to phenotype variations of 22q11.2 microdeletion/duplication syndromes as genomic modifiers.
authors.affiliation: Department of Pathology, University of Miami Miller School of Medicine, Miami, FL 33136, USA. yfan@med.miami.edu.
authors.forename: Deling
authors.initials: D
authors.lastname: Li
authors.forename: Mustafa
authors.initials: M
authors.lastname: Tekin
authors.forename: Maria
authors.initials: M
authors.lastname: Buch
authors.forename: Yao-Shan
authors.initials: YS
authors.lastname: Fan