Classic bladder exstrophy: Frequent 22q11.21 duplications and definition of a 414 kb phenocritical region

Background: Classic bladder exstrophy (CBE) is the most common form of the bladder exstrophy and epispadias complex. Previously, we and others have identified four patients with a duplication of 22q11.21 among a total of 96 unrelated CBE patients. Methods: Here, we investigated whether this chromosomal aberration was commonly associated with CBE/bladder exstrophy and epispadias complex in an extended case-control sample. Multiplex ligation-dependent probe amplification and microarray-based analysis were used to identify 22q11.21 duplications in 244 unrelated bladder exstrophy and epispadias complex patients (including 217 CBE patients) and 665 healthy controls. Results: New duplications of …