Reduced birth weight, cleft palate and preputial abnormalities in a cloned dog

Abstract

The aim of the present study was to report a novel developmental abnormality in a cloned dog. A fibroblast cell line was established from an 8-year-old male German shepherd dog. In vivo matured oocytes were retrieved from a large breed dog, and the nucleus was removed from each oocyte. A donor cell was injected into an enucleated oocyte, and the oocyte-cell couplet was fused electrically. After chemical activation, the resulting embryos were transferred into a naturally estrus-synchronized recipient dog, and two cloned pups were delivered by Cesarean section 60 days later. One cloned pup (Clone 1) was healthy, but the other (Clone 2) had a birth weight of only 320 g and cleft palate, failure of preputial closure at the ventral distal part, and persistent penile frenulum. Clone 2 was raised by stomach feeding until Day 40 after birth, where palatoplasty was performed. The abnormalities in external genitalia in Clone 2 resulted in persistent penile extrusion that was surgically corrected. This complex developmental abnormality has not been reported in dogs previously.

Health and temperaments of cloned working dogs

“…Consequently, the resulting cloned puppy had the same nuclear and mitochondrial genetic information as the cell donor and oocyte donor, respectively [ 8 29 37 42 ]. Since that first cloned dog, a variety of cloned dogs have been produced, and it has been reported that dog cloning using the SCNT technique can be successfully performed regardless of the sex (male [ 36 ] and female [ 25 ]), age (fetus [ 18 ], young adult [ 36 ], and old [ 24 ]), or breed (Afghan hound [ 25 36 ], miniature poodle [ 24 ], beagle [ 18 29 ], Labrador Retriever [ 35 43 ], Pekingese [ 46 ], German Shepherd [ 30 42 ], Sapsaree [ 23 ], and Gyeongju Donggyeong dog [ 8 ]) of the cell donor.…”

Ectopic liver and gallbladder in a cloned dog: Possible nonheritable anomaly

“…The "large offspring syndrome" characterized by fetal and placental overgrowth or other anomalies include respiratory distress, major cardiovascular abnormalities, and enlargement of organs are commonly seen in cloned ruminants [49]. Compared to observations in ruminants, there have been few studies related to congenital abnormalities in cloned dogs; placentomegaly [50], malformations [32], cleft palate and preputial abnormalities [51], and defects in the anterior abdominal wall, increased heart and liver sizes, muscle mass, and macroglossia have all been reported [52]. Aberrant epigenetic reprogramming in DNA methylation, histone acetylation, and X-chromosome inactivation have been proposed as the cause of developmental anomalies seen in cloned animals [53].…”

Dog cloning—no longer science fiction

“…Cloning dogs by SCNT is a highly effective way of producing dogs with exceptional skills, as they are identical to those of cell donor dogs except the mitochondrial genome. For instance, the elite cloned dogs with high ability for drug detection in airport/quarantine areas or rescuing human in disaster fields have been successfully generated (Kim et al, , ; Oh et al., , ). Furthermore, their ability to sniffing drugs was evaluated (Choi et al., ), and all of the cloned dogs with identical genomic backgrounds were selected as a drug detection dogs.…”