title: Preimplantation genetic diagnosis for chromosomal rearrangements with the use of array comparative genomic hybridization at the blastocyst stage.
abstract: To establish the value of array comparative genomic hybridization (CGH) for preimplantation genetic diagnosis (PGD) in embryos of translocation carriers in combination with vitrification and frozen embryo transfer in nonstimulated cycles.
  
  
  
  Retrospective data analysis study.
  
  
  
  Academic centers for reproductive medicine and genetics.
  
  
  
  Thirty-four couples undergoing PGD for chromosomal rearrangements from October 2013 to December 2015.
  
  
  
  Trophectoderm biopsy at day 5 or day 6 of embryo development and subsequently whole genome amplification and array CGH were performed.
  
  
  
  This approach revealed a high occurrence of aneuploidies and structural rearrangements unrelated to the parental rearrangement. Nevertheless, we observed a benefit in pregnancy rates of these couples.
  
  
  
  We detected chromosomal abnormalities in 133/207 embryos (64.2% of successfully amplified), and 74 showed a normal microarray profile (35.7%). In 48 of the 133 abnormal embryos (36.1%), an unbalanced rearrangement originating from the parental translocation was identified. Interestingly, 34.6% of the abnormal embryos (46/133) harbored chromosome rearrangements that were not directly linked to the parental translocation in question. We also detected a combination of unbalanced parental-derived rearrangements and aneuploidies in 27 of the 133 abnormal embryos (20.3%).
  
  
  
  The use of trophectoderm biopsy at the blastocyst stage is less detrimental to the survival of the embryo and leads to a more reliable estimate of the genomic content of the embryo than cleavage-stage biopsy. In this small cohort PGD study, we describe the successful implementation of array CGH analysis of blastocysts in patients with a chromosomal rearrangement to identify euploid embryos for transfer.
authors: Ghent Fertility and Stem Cell Team, Department for Reproductive Medicine, Ghent University Hospital, Ghent, Belgium. Electronic address: christodoulos.christodoulou@uzgent.be.
authors: Christodoulos
authors: C
authors: Christodoulou
authors: Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium.
authors: Annelies
authors: A
authors: Dheedene
authors: Ghent Fertility and Stem Cell Team, Department for Reproductive Medicine, Ghent University Hospital, Ghent, Belgium.
authors: Björn
authors: B
authors: Heindryckx
authors: Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
authors: Filip
authors: F
authors: van Nieuwerburgh
authors: Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
authors: Dieter
authors: D
authors: Deforce
authors: Ghent Fertility and Stem Cell Team, Department for Reproductive Medicine, Ghent University Hospital, Ghent, Belgium.
authors: Petra
authors: P
authors: De Sutter
authors: Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium.
authors: Björn
authors: B
authors: Menten
authors: Ghent Fertility and Stem Cell Team, Department for Reproductive Medicine, Ghent University Hospital, Ghent, Belgium.
authors: Etienne
authors: E
authors: Van den Abbeel
mesh_terms: D001706:Biopsy; D001755:Blastocyst / Q000473:pathology*; D002869:Chromosome Aberrations; D025063:Chromosome Disorders / Q000175:diagnosis* / Q000209:etiology / Q000235:genetics; D002877:Chromosomes, Human; D055028:Comparative Genomic Hybridization; D015925:Cryopreservation; D046149:Embryo Culture Techniques; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects*; D015321:Gene Rearrangement; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing; D006801:Humans; D050498:Live Birth; D010641:Phenotype; D011003:Ploidies; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D019836:Preimplantation Diagnosis / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome; D058989:Vitrification
keywords: Preimplantation genetic diagnosis (PGD); array CGH; blastocysts; chromosomal rearrangements; trophectoderm biopsy