Cleft palate in a cloned dog

다국어 초록 (Multilingual Abstract)

Cleft palates with or without cleft lip is one of the most common congenital craniofacial defects in dogs. It has been reported that monogenic autosomal recessive inheritance caused this defect in this species. However, here, we aimed to report cleft palate in a cloned dog. A fibroblast cell line was established from skin tissues of an eight-year-old German shepherd dog. Blood was collected from oocyte donor dogs, and serum progesterone concentration was measured by chemiluminescence enzyme immunoassay method. Ovulation was determined when serum progesterone results reached 5-10 ng/ml, and in vivo matured oocytes were collected surgically about 72 hr after ovulation. Donor cells were cultured with Dulbecco’s modified Eagle medium supplemented with 10% (v/v) fetal bovine serum until confluence. An in vivo matured oocyte was enucleated, and a donor cell was injected into the perivitelline space. The oocyte-cell couplet was electrically fused, and chemically activated. Reconstructed embryos were transferred to an oviduct of a recipient. Pregnancy diagnosis was performed 27 days after the embryo transfer, and ultrasonography of fetal heart beat, and rectal temperature and serum progesterone value of recipient was monitored until the day of delivery. Microsatellite analysis was performed using genomic DNA of cell donor, clones, and oocyte donors. As results, a total of 74 cloned embryos were transferred to five recipients, and one recipient diagnosed as pregnant with two fetuses by ultrasonography and radiology. Caesarean section was performed on day 58 after embryo transfer due to a decreased heart beat of a fetus, which was lower than 180. Two cloned puppies with 640g and 320g of birth weight were delivered safety, but the small one was born with a cleft palate. Microsatellite analysis results of both clones were identical with the cell donor. Cleft palate of the clone was surgically corrected on day 40 after birth. To our knowledge, there has been no report about cleft palate in cloned dogs, and also, no report about clones with different phenotype of cleft palate in dogs. Therefore, this study can give a clue of cleft palate in dogs, which might not be a genetic cause. Further studies about aberrant epigenetic reprogramming in those clones are needed.