title: Breakpoint analysis of the recurrent constitutional t(8;22)(q24.13;q11.21) translocation.
abstract: BACKGROUND
  The t(8;22)(q24.13;q11.2) has been identified as one of several recurrent constitutional translocations mediated by palindromic AT-rich repeats (PATRRs). Although the breakage on 22q11 utilizes the same PATRR as that of the more prevalent constitutional t(11;22)(q23;q11.2), the breakpoint region on 8q24 has not been elucidated in detail since the analysis of palindromic sequence is technically challenging.
  
  
  RESULTS
  In this study, the entire 8q24 breakpoint region has been resolved by next generation sequencing. Eight polymorphic alleles were identified and compared with the junction sequences of previous and two recently identified t(8;22) cases . All of the breakpoints were found to be within the PATRRs on chromosomes 8 and 22 (PATRR8 and PATRR22), but the locations were different among cases at the level of nucleotide resolution. The translocations were always found to arise on symmetric PATRR8 alleles with breakpoints at the center of symmetry. The translocation junction is often accompanied by symmetric deletions at the center of both PATRRs. Rejoining occurs with minimal homology between the translocation partners. Remarkably, comparison of der (8) to der(22) sequences shows identical breakpoint junctions between them, which likely represent products of two independent events on the basis of a classical model.
  
  
  CONCLUSIONS
  Our data suggest the hypothesis that interactions between the two PATRRs prior to the translocation event might trigger illegitimate recombination resulting in the recurrent palindrome-mediated translocation.
authors.affiliation: Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Aichi, Japan.
authors.forename: Divya
authors.initials: D
authors.lastname: Mishra
authors.affiliation: Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Aichi, Japan.
authors.forename: Takema
authors.initials: T
authors.lastname: Kato
authors.affiliation: Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Aichi, Japan.
authors.forename: Hidehito
authors.initials: H
authors.lastname: Inagaki
authors.affiliation: Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto 390-8621, Nagano, Japan.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Kosho
authors.affiliation: Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto 390-8621, Nagano, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Wakui
authors.affiliation: Department of Pediatrics, Dokkyo Medical University Koshigaya Hospital, Koshigaya 343-8555, Saitama, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kido
authors.affiliation: Department of Pediatrics, Dokkyo Medical University Koshigaya Hospital, Koshigaya 343-8555, Saitama, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Sakazume
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Taniguchi-Ikeda
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Morisada
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Hyogo, Japan.
authors.forename: Kazumoto
authors.initials: K
authors.lastname: Iijima
authors.affiliation: Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto 390-8621, Nagano, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Fukushima
authors.affiliation: Division of Human Genetics, The Children's Hospital of Philadelphia, Philadelphia 19104, PA, USA.|Department of Pediatrics, The Perelman School of Medicine of the University of Pennsylvania, Philadelphia 19104, PA, USA.
authors.forename: Beverly S
authors.initials: BS
authors.lastname: Emanuel
authors.affiliation: Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake 470-1192, Aichi, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kurahashi
keywords: PATRR; Palindrome-mediated translocation; Supernumerary der(8)t(8;22); t(8;22)