Developmental Ability of CD-1 Strain Mouse Embryos In Vitro and In Vivo with the Different Glucose Phosphate Isomerase Patterns.

Abstract
Glucose phosphate isomerase (GPI)-1AA and GPI-1BB homozygotes were produced by natural mating of CD-1 strain mice and the several reproductive characteristics of both homozygotes were compared. The pregnancy rate, period required for copulation and litter size were essentially the same. The developmental ability of GPI-1AA zygotes and 2-cell embryos in vitro was significantly lower than that of GPI-1BB (60 vs 75% and 75 vs 98%, respectively). After preservation at 4C for 24 h, the proportion of the GPI-1AA-2-cell embryos developed to blastocysts was significantly low (28 vs 57%). After transfer of GPI-1AA embryos to recipient mice, the developmental potential into fetus was similar or significantly superior to that of GPI-1BB (19 vs 24% and 47 vs 14%, respectively). When both embryos were aggregated at the 8-16-cell stage and transferred to recipients, 76% of the young (13/17) was chimeras and both isozymes types were observed in most tissues analyzed. In conclusion, both GPI-1AA and GPI-1BB embryos of the CD-1 strain mice were equally useful for researches in developmental biology and biotechnology, their features being basically the same.