Developmental potential of microbiopsied murine blastocysts

OBJECTIVE: To evaluate the frequency of mouse pups born following blastocyst biopsy and embryo transfer compared to nonbiopsied controls. METHODS: ICR Swiss albino and C57B1/6 mice served as embryo donors. Pregnant mare serum gonadotropin treatment was followed 46-52 hours later by hCG, when donors were paired with fertile males. Mating was confirmed the following day and embryos were collected on the afternoon of day 4. After overnight culture, hatching trophoblast was excised by micromanipulation with a fine-pulled glass pipette. Embryos (206 controls, 206 biopsied) were transferred to 26 pseudopregnant recipients. Alternate mouse strains were used to identify pups born from control or biopsied embryos. RESULTS: The end point was percentage of pups born ((number born/number transferred) x 100), using angular transformation before analysis. There was no significant difference (P > .1) between percent live-born in control (27.7%) or biopsied (34.5%) embryos, nor were there any strain differences. CONCLUSION: These data support the hypothesis that the developmental potential of murine blastocysts is not affected adversely by the biopsy procedure.