A total of 611 reconstructed oocytes were produced via SCNT
using ATM gene-targeted fetal fibroblasts. These cloned embryos
were surgically transferred to five surrogate gilts. Early pregnancies were observed in three gilts, and two ultimately went to full
term. Five cloned piglets were delivered, four from one surrogate
and one from the other (
Fig. 3
). To confirm whether the cloned pig-
lets were derived from the nuclear donor cells, genomic DNA
extracted from tail biopsies was screened by PCR and Southern
blot. As shown in
Fig. 4
, all piglets contained one allele of the
ATM gene disrupted by PGK-Neo, resulting in an increased size
of ATM gene fragment in PCR and in Southern blot