title: Confirmation rates of array-CGH in day-3 embryo and blastocyst biopsies for preimplantation genetic screening.
abstract: OBJECTIVE
  The purpose of this study was to compare the confirmation rate of day-3 embryo biopsy (blastomere) and trophectoderm biopsy using array-comparative genomic hybridization (array-CGH) technology.
  
  
  METHODS
  A blinded study was conducted to re-analyse 109 embryos previously diagnosed as chromosomally abnormal by array-CGH. Preimplantation genetic screening (PGS) was performed using array-CGH on day 3 (n = 50) or day 5 (n = 59). Partial chromosome gains or losses were excluded (n=6), and only whole chromosome aneuploidies were considered. Re-analysis of whole blastocysts was carried out following the same array-CGH protocol used for PGS.
  
  
  RESULTS
  The PGS result was confirmed in the whole blastocyst in (a) 49/50 (98 %) abnormal embryos after day-3 biopsy and (b) 57/59 (96.6 %) abnormal embryos after trophectoderm biopsy. One embryo (1/50; 2 %) was diagnosed as abnormal, with monosomy 18, on day 3, and software analysis of the whole blastocyst gave a euploid result; however, a mosaic pattern was observed for monosomy 18 in the whole blastocyst. Two trophectoderm biopsy cases (3.4 %) did not have the abnormalities (trisomy 7, and trisomy 1 and 4, respectively) verified in the whole embryo. Concordance rates for both biopsy strategies and for individual chromosomes were evaluated by Fisher's exact test and showed no significant differences.
  
  
  CONCLUSIONS
  Both types of biopsies showed similar high concordance rates with whole blastocyst results. Therefore, regarding the confirmation rates shown in this work, day-3 embryo biopsies can be representative of the whole embryo and both types of biopsy can be used for clinical analysis in PGS following the described array-CGH protocol.
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain. pere.mir@igenomix.com.
authors.forename: P
authors.initials: P
authors.lastname: Mir
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Mateu
authors.affiliation: IVI-Valencia, Pza.Policía Local, 3, 46015, Valencia, Valencia, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Mercader
authors.affiliation: IVI-Zaragoza, Poetisa María Zambrano, 31, 50018, Zaragoza, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Herrer
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Rodrigo
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Vera
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Peinado
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Milán-Sánchez
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Campos-Galindo
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.
authors.forename: S
authors.initials: S
authors.lastname: García-Herrero
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.|IVI-Valencia, Pza.Policía Local, 3, 46015, Valencia, Valencia, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Simón
authors.affiliation: IGENOMIX, Parc Científic de la Universitat de Valéncia, C/Catedrático Agustín Escardino, 9, 46980, Paterna, Valencia, Spain.|IVI-Valencia, Pza.Policía Local, 3, 46015, Valencia, Valencia, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Rubio
mesh_terms: D001706:Biopsy; D001755:Blastocyst / Q000166:cytology*; D002869:Chromosome Aberrations; D055028:Comparative Genomic Hybridization / Q000379:methods*; D004624:Embryo Transfer; D047108:Embryonic Development / Q000235:genetics*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D011247:Pregnancy; D019836:Preimplantation Diagnosis
keywords: Array-CGH; Embryo biopsy; False-positive rate; Mosaicism; Preimplantation