Experimental attempts to extend the current preimplantation genetic diagnosis with individual karyotypization of human blastomeres.
The drug-induced chromosome condensation using okadaic acid, a potent protein phosphatase inhibitor, was studied in day 1 to day 4 (D1-D4) spare human preimplantation embryos. In order to obtain cells for genetic tests, we developed a modified displacement blastomere biopsy method. During the okadaic acid treatment, approximately 40% of biopsied cells were lost due to heavy changes of the plasma membrane; this detrimental effect of okadaic acid differed markedly with the respect to the age of embryos. In comparison with the natural embryonic mitotic index, day 1 and day 2 embryonic cells gave increased yields of chromosome spreads (up to 51% of the initial D1-D2 cell number); on days 3 and 4 we were not able to obtain from surviving cells more than 31% blastomeres with condensed chromosomes (9% of total D3-D4 cell number). All chromosome spreads were successfully used for recycling in G-banding and subsequent FISH analysis.
Hlinka
D
D
Assisted Reproduction Center, L. Pasteur University Hospital, Kosice, Slovak Republic.
Dudás
M
M
Herman
M
M
Kalina
I
I
D001706:Biopsy; D001757:Blastomeres / Q000187:drug effects / Q000502:physiology*; D002871:Chromosome Banding; D002877:Chromosomes, Human / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D007621:Karyotyping; D019319:Okadaic Acid / Q000494:pharmacology; D011003:Ploidies; D019836:Preimplantation Diagnosis
D004791:Enzyme Inhibitors; D019319:Okadaic Acid