Compared to their IVF counterparts, SCNT embryos
exhibit aberrant gene expression due to incomplete
epigenetic reprogramming [26], which results in adverse
effects on their development [27]. DNA methylation is
considered as one of the most important epigenetic events
due to its ability to reversibly repress the genes. We found
the opposite pattern in relative expression level of DNMT1,
DNMT3a, HDAC1, and IGF-1R genes in the donor cells and in
embryos produced from them. It was higher in lymphocytes
than in skin fibroblasts whereas, in the embryos, it
was higher in skin fibroblast- than in lymphocyte-derived
blastocysts suggesting that because of reprogramming,
the epigenetic status and gene expression pattern of donor
cells may not be reflected in the cloned embryos produced
from them. Another possible reason for the lower development
of blastocysts from lymphocyte-derived embryos
could be the lower expression of development-related gene
IGF-1R in these embryos