title: Heteroparental blastocyst production from microsurgically corrected tripronucleated human embryos.
abstract: OBJECTIVE
  To prove the efficiency of identification and removal of one of the surplus paternal pronuclei in dispermic IVF zygotes to obtain heteroparental blastocysts.
  
  
  METHODS
  Experimental.
  
  
  METHODS
  One hundred fourteen tripronucleated (3PN) embryos from conventional IVF.
  
  
  METHODS
  After informed and signed consent, the patients from Instituto Valenciano Infertilidad (IVI), Valencia, donated their abnormally fertilized embryos.
  
  
  METHODS
  Seventy-two embryos were diploidized by microsurgical removal of the pronucleus located at the farthest position to the second polar body. Forty-two 3PN embryos served as controls.
  
  
  METHODS
  Survival and correction rate; in vitro development up to the blastocyst stage; X, Y, and 18 chromosome determination by triple fluorescent in situ hybridization and, inheritance analysis for 10 polymorphic repeat regions using polymerase chain reaction (PCR) amplification and sequencing.
  
  
  RESULTS
  Seventy-eight percent of 3PN zygotes (56/72) survived manipulation and eventually 51 zygotes had two pronuclei (71%). Forty-one percent of manipulated embryos progressed in vitro to the blastocyst stage (21/51). Fluorescent in situ hybridization analysis performed on eight manipulated embryos confirmed their diploid state; all four controls were triploid. Heteroparental inheritances were also confirmed in four of six manipulated embryos.
  
  
  CONCLUSIONS
  Heteroparental blastocysts can be derived from corrected dispermic zygotes.
authors.affiliation: IVI Foundation, IVI University, Valencia, Spain. mjescriba@ivi.es <mjescriba@ivi.es>
authors.forename: María-José
authors.initials: MJ
authors.lastname: Escribá
authors.forename: Julio
authors.initials: J
authors.lastname: Martín
authors.forename: Carmen
authors.initials: C
authors.lastname: Rubio
authors.forename: Diana
authors.initials: D
authors.lastname: Valbuena
authors.forename: José
authors.initials: J
authors.lastname: Remohí
authors.forename: Antonio
authors.initials: A
authors.lastname: Pellicer
authors.forename: Carlos
authors.initials: C
authors.lastname: Simón
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000166:cytology*; D002467:Cell Nucleus / Q000235:genetics; D002469:Cell Separation / Q000379:methods*; D002869:Chromosome Aberrations; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged