DOES CA2+ MG2+-FREE MEDIUM HAVE AN EFFECT ON THE SURVIVAL OF THE PREIMPLANTATION MOUSE EMBRYO AFTER BIOPSY/

The way in which the different technical aspects of clinical preimplan tation genetic diagnosis affect the survival of the biopsied embryo is not well understood. One of these aspects is the influence of Ca2+/Mg 2+-free medium on the developmental capacity of the biopsied embryo an d the biopsied cell itself. Therefore, we used an experimental design involving 4-cell mouse embryos to evaluate the effect of performing th e biopsy procedure under such conditions. Our results indicate that th e use of Ca2+/Mg2+-free medium has no detrimental effect (at least in mouse embryos) on the viability of the biopsied embryos and their biop sied cells when used during relatively short times of exposure.