title: Assessment of beta-HCG, beta-LH mRNA and ploidy in individual human blastomeres.
abstract: 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.
authors.affiliation: 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
authors.forename: Christoph
authors.initials: C
authors.lastname: Hansis
authors.forename: James A
authors.initials: JA
authors.lastname: Grifo
authors.forename: YaXu
authors.initials: Y
authors.lastname: Tang
authors.forename: Lewis C
authors.initials: LC
authors.lastname: Krey
mesh_terms: 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*
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; D017931:DNA Primers; D018076:DNA, Complementary; D037101:Luteinizing Hormone, beta Subunit; D012333:RNA, Messenger