Heteroparental blastocyst production from microsurgically corrected tripronucleated human embryos.
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.
Escribá
María-José
MJ
IVI Foundation, IVI University, Valencia, Spain. mjescriba@ivi.es <mjescriba@ivi.es>
Martín
Julio
J
Rubio
Carmen
C
Valbuena
Diana
D
Remohí
José
J
Pellicer
Antonio
A
Simón
Carlos
C
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