Assessment of beta-HCG, beta-LH mRNA and ploidy in individual human blastomeres.
In human embryos, blastomeres differentiate into trophectoderm (TE) cells and inner cell mass (ICM) cells of blastocysts. Although morphologically indistinguishable, blastomeres at early cleavage stages are likely to undergo changes on a molecular level that make them destined to become ICM or TE cells. While the transcription factor Oct-4 might serve as a marker for totipotent ICM cells, human chorionic gonadotrophin might be used as the equivalent for TE cells. This study reports a reverse transcription-polymerase chain reaction procedure to assess human beta-HCG mRNA concentrations as well as ploidy in individual blastomeres from normally and abnormally fertilized human embryos. beta-HCG mRNA was detected in both euploid and aneuploid cells and in oocytes. Surprisingly, beta-LH mRNA was also detected in some euploid blastomeres. In regard to preimplantation genetic diagnosis, assessment of expression levels of beta-HCG and Oct-4 mRNA in individual biopsied cells might serve as a tool to identify embryogenic blastomeres in combination with testing for chromosome and single gene abnormalities.
Hansis
Christoph
C
Program for In Vitro Fertilization, Reproductive Surgery and Infertility, New York University School of Medicine, 660 First Avenue, 5th floor, New York, NY 10016, USA. ChrHansis@aol.com
Grifo
James A
JA
Tang
YaXu
Y
Krey
Lewis C
LC
D001483:Base Sequence; D001757:Blastomeres / Q000502:physiology*; D002467:Cell Nucleus / Q000235:genetics; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000235:genetics*; D003593:Cytoplasm / Q000235:genetics; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D004622:Embryo, Mammalian / Q000502:physiology; D005314:Embryonic and Fetal Development / Q000235:genetics*; D005307:Fertilization in Vitro; D006801:Humans; D007621:Karyotyping; D037101:Luteinizing Hormone, beta Subunit / Q000235:genetics*; D009865:Oocytes / Q000166:cytology; D011003:Ploidies; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000235:genetics*
D018997:Chorionic Gonadotropin, beta Subunit, Human; D017931:DNA Primers; D018076:DNA, Complementary; D037101:Luteinizing Hormone, beta Subunit; D012333:RNA, Messenger