Figure 3.

Birth (A) and placental (B) weights of ES cell-derived and control neonatal mice. Birth and placental weights of clones were significantly higher than either ES cell-tetraploid mice (P < 0.0001 for both weights) or in vitro-cultured controls (P < 0.0001 for both weights) in pair-wise comparisons. Neither birth nor placental weights of ES cell-tetraploid mice were significantly different from in vitro-cultured controls (P > 0.05 for both weights). Birth and placenta weights of normal mice were significantly lower than cloned, ES cell-tetraploid or in vitro-cultured pups (for all P < 0.004). Pairwise comparisons were performed by using the Student's t test. Data from normal pups were recorded from litters with a size less than or equal to three. Cross-bars mark the mean weight for each data set. In vitro-cultured, control animals were generated by isolating two-cell stage embryos, culturing them to the blastocyst stage, and then transferring them to recipient females.