Antibiotic selectable marker genes have been widely used to generate transgenic animals. Once transgenic animals have been obtained, the selectable marker is no longer necessary but raises public concerns regarding biological safety. The aim of this study was to prepare competent antibiotic selectable marker free transgenic cells for somatic cell nuclear transfer (SCNT). PhiC31 intergrase was u...

The development of an efficient transfection system in livestock cells is an important step towards investigating gene transfer and the functioning and production of transgenic animals. Important factors involved in cationic liposome mediated gene transfer were evaluated through in vitro transfection of bovine, caprine and ovine fibroblast cells. Transfection of plasmid DNA complexes of differe...

Nuclear transfer (NT) is a procedure by which genetically identical individuals can be created. The technology of pig somatic NT, including in vitro maturation of oocytes, isolation and treatment of donor cells, artificial activation of reconstructed oocytes, embryo culture and embryo transfer, has been intensively studied in recent years, resulting in birth of cloned pigs in many labs. While i...

Multiple genetic modifications in pigs can essentially benefit research on agriculture, human disease and xenotransplantation. Most multi-transgenic pigs have been produced by complex and time-consuming breeding programs using multiple single-transgenic pigs. This study explored the feasibility of producing multi-transgenic pigs using the viral 2A peptide in the light of previous research indic...

Polyploidy has many advantages over diploidy, such as rapid growth, sterility, and disease resistance, and has been extensively applied in agriculture and aquaculture. Though generation of new polyploids via polyploidization has been achieved in plants by different ways, it is comparatively rare in animals. In this article, by a chemical compound, SP600125, polyploidization is induced in fish c...

The ability to produce transgenic animals through the introduction of exogenous DNA has existed for many years. However, past methods available to generate transgenic animals, such as pronuclear microinjection or the use of embryonic stem cells, have either been inefficient or not available in all animals. More recently, somatic cell nuclear transfer has provided a method to create transgenic a...

Background: Successful in vitro maturation (IVM) of oocytes is an important step for production of livestock through assisted reproductive techniques including somatic cell nuclear transfer (SCNT). Obtaining an optimal duration for maturation of oocyte is essential, since over exposure to maturation medium results in oocyte aging, while under exposure leads to production of immature incompetent...

Recent advances in genomics provide genetic information from humans and other mammals (mouse, rat, dog and primates) traditionally used as models as well as new candidates (pigs and cattle). In addition, linked enabling technologies, such as transgenesis and animal cloning, provide innovative ways to design and perform experiments to dissect complex biological systems. Exploitation of genomic i...

It is generally considered that animal cloning by nuclear transfer originated in proposals made by Hans Spemann (1936), following his experiments on delayed nucleation in the newt egg, which were preceded by similar attempts using the sea-urchin egg (Loeb, 1894). Briggs and King (1952) were the first to succeed in transplanting blastula and gastrula nuclei into the enucleated frog egg and in ob...

Reprogramming of somatic cells to a pluripotent embryonic stem cell-like state has been achieved by nuclear transplantation of a somatic nucleus into an enucleated egg and most recently by introducing defined transcription factors into somatic cells. Nuclear reprogramming is of great medical interest, as it has the potential to generate a source of patient-specific cells. Here, we review strate...