The application of gene cloning technology, the latest progress of gene cloning.

When it comes to the word "clone", many people will think of the world's first animal to be bred using this technology- cloned sheep "Dolly", which marks the biological body through sotic cells for asymmetric reproduction cloning technology become a reality.
, cloned pigs, cloned cattle and so on came out, cloned dogs did not come out until 2005.
is widely regarded by the scientific community as one of the most difficult animals to clone, and technology in this field has long been monopolized by South Korea.
The Chinese Academy of Sciences Guangzhou Institute of Biomedicine and Health Lai Liangxuan researcher led the Hino Valley research team and Guangzhou Institute of Biology laboratory team, with the help of Cas9 gene editing technology, first obtained two gene editing dogs "apple" and "hulu", after which, researchers to "apple" body cells as clone dog feeder cells, optimize the cloning technology platform, break through the technical bottleneck, successfully cultivate "apple" cloned dog "dragon".
marks china's second independent mastery of canine cell cloning technology after South Korea.
canine cell cloning difficulties in 2005 the world's first sotic cell cloning dog "Snoopy" was born in South Korea, since then, canine cell cloning technology has been in the hands of South Koreans, has never been broken by other countries.
cloned dogs are a worldwide problem and face many difficulties: the first question is how to obtain a sufficient number of mature ovaries.
pigs, cattle, sheep and other animals through in vitro maturation culture technology can obtain a large number of mature ovary cells, and canine ovary in vitro mature culture efficiency is very low, can only obtain mature ovary cells from the body.
acquisition of mature ovary cells in the body requires a precise grasp of the ovulation time of the dog, and once missed a hair ovulation time, it is necessary to wait for the first half of the year or a year before the next opportunity.
it is very difficult to accurately grasp the ovulation time, and it is difficult to establish a unified evaluation criterion by serum to determine the difference between progesterone individuals.
is premature, the ovaries are immature, and the ovaries age too late.
how to accurately grasp the ovulation time of dogs is the key to obtaining high-quality mature ovary cells.
second, a dog ovulates an average of 7-8 eggs, discharges the eggs in the GV period, need to stay in the fallopian tubes 48-72h to reach the MII. period.
ovary cells are rich in lipids, darker colors, great viscosity, more difficult microoperation, sotic cell electrical fusion efficiency is not high.
, it is difficult to maintain consistency in reproductive physiological stage between receptors and feeders in dog embryo transfer.
low pregnancy rate, coupled with the inefficiency of cloning technology itself, makes canine cell cloning more difficult, requiring a lot of financial, human and material resources.
gene editing, magic scissors 2013 a new gene editing technology (CRISPR/Cas9) is popular all over the world, it has the characteristics of simple and convenient construction, gene targeting efficiency.
how amazing is it? It allows genes to be desired, not to be desired, and to be genetically modified in animals and human embryos such as cattle, sheep, pigs, rabbits, mice, rats, etc.
can it also play a role in the dog genome? With this curiosity, we started researching dog gene editing in 2013.
the experimental process was not as smooth as originally designed, and a year's effort did not achieve the desired results.
after several twists and turns, several changes to the experimental program, the magic scissors finally played a magical function, in late June 2014, the world's first gene (MSTN) knocked out the dog "Hercules" and "Heavenly Dog" was born.
the last four months, Hercules and Sky Dog showed great athletic ability, and "Sky Dog" also has obvious "bi-muscle" characteristics.
Magic Scissors continues to write its magic, in October 2016, we set out to remove the dog APOE gene, with the previous basic research, the experiment went very smoothly, December 29, 2016, the world's first atherosclerosis model dog "apple" was born.
20 days later, another APOE gene knockout dog, Hulu, was born.
story is still playing out, and magical scissors are creating new magic.
the latest developments in gene cloning: the fascinating story from the world's first genetic knockout dog to the gene knockout soy cell clone dog has yet to be told since 2012.
the original idea was to do genetic knockout soy cell clones, which was almost zero for us, and the only resource was some articles published by Koreans without specific details.
, the dog's emotional ovulation time identification are confused, we after a year of continuous exploration, only gradually grasp the law.
previous sotrocy cloning experiments were not successful due to poor foundation and limitation of experimental conditions in the early stage.
2013, crispr/Cas9, the third generation of the latest gene editing technology, was in full swing, and we first thought of applying this technology to dog gene editing.
nearly a year of hard work, the world's first muscle growth inhibitor gene knockout dog was born.
"Hercules" and "Day Dog" the birth, so that everyone on the team is very excited, everyone's efforts and persistence in exchange for the ultimate success.
took more than two years from start to start to succeed.
these two years, we have experienced repeated failures, and it is the continuous reflection and improvement of failure, perseverance, before the ultimate success.
the road of scientific research, it is necessary to have a spirit of not ysting to lose.
gene-editing dogs, but somato-cell cloning has not been successful, Lai Liangxuan researchers led the Beijing Hino Valley research and development team and Guangzhou Institute of Biology laboratory team to continue to overcome this worldwide problem.
mentioned the world's first genetic knockout clone dog "Dragon", but also from its feeder "Apple" to start.
"Apple" was born on December 29, 2016, and is a gene-editing dog that knocks out the APOE gene using Cas9 technology.
"Apple" was born, its skin cells were preserved, and then the researchers used "apple" cells for soy cell cloning, after several experiments, on May 28, 2017, the world's first gene knockout sotic cell clone dog "Dragon" was born, and then two other similar cloned dogs were born.
this marks china's second independent mastery of canine cell cloning technology after South Korea, and the first time to achieve canine gene knockout soy cell cloning.
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