Who I tried to clone a human being, and what came of it
Cats and mice, lizards and frogs, monkeys and even mammoths – who just did not try to reproduce scientists for more than a hundred-year experiment history. The 2019 Hero was a cloned garlic kitten, which turned out to be very unlike the original. Stories of this and other amazing clones – in the material "My Planet".
How it works
The term "clone" first used the British biologist John Haldain in the middle of the XX century. At first, the group of plants obtained as a result of the growing season was so called, and later the definition began to apply to each individual copy. Now clones are given any organisms, genetically identical prototype.
They are obtained in two ways: the separation of embryonic cells in the early stages of development and the method of transferring the kernel. In the latter case, the kernel is removed from the egg, replacing it with the core of somatic (non-comb) cells of that organism that they want to clone. The developed embryo is attached to the Makeup of females, and if everything goes according to plan, a clone appears on the light. When cloning pets, only 5% of such attempts are successful, in the case of wild animals, this figure is even lower – only 1%. Problems arise at the "launch" stage of the nucleus, and during intrauterine development, and immediately after birth.
Amoebs and Potatoes: Clones in Nature
What humanity is difficult to be difficult through samples and errors, long-invented by nature: copies with an identical set of genes occur when a bunch of reproduction of plants and animals. Clones flourish in gardens and gardens: it is they who develop strawberry or potato tubers. Many mushrooms, Mukhov, yeast, some sponges and worms "Dubli" are formed from the kidneys – the emergence on the body of the source body. And the simplest example of natural cloning – amoeba division. Genetic copies occur during parthenogenesis – one of the types of sexual reproduction in animals with a double set of chromosomes. In this case, females-clones appear from eggs without fertilization: for example, a steppe dob – a large grasshopper.
Already in the 21st century, biologists have found that marine hedgehogs can clone themselves: when they approach large predators, they either grow kidney from which a full-fledged embryo appears, or they simply share. Two smaller individuals are less noticeable for prey fish, and the duplicated genetic material has more chances for playback.
Sea hedgehog: Life in the laboratory
It is the marine hedgehogs that became the participants of the first successful experiments on cloning. In 1885, the German biologist Hans Drish began to study the reproduction methods on the example of these oscalker and other animals with large egg cells. He found out that isolated seabed embryos cells can develop in small larvae. And in 1902 the scientist raised two full-fledged individuals, dividing one embryo in half at the first stages of growth. A year earlier, his compatriot Hans Speman did the same with Salamandra: He divided the two-cell germ and got a new organism from each halves. As a result, science has become known that the required amount of information for further development is in each embryo cell.
Sheep Dolly: At the Peak of Glory
Just like the squirrel and the arrow were not pioneers in space, Dolly was neither the first clone nor even the first cloned mammal – she was preceded by successful copies of frogs and mice, cows and sheep. But all the glory got exactly this lamb. It is not by chance that in 1996 the core for the first time they first took an adult animal from the frozen breast cell, and the experience was crowned with success. Prior to this, when cloning into the egg, the kernel was moved, taken either from another egg, or in the embryo. In the experiment with dolly from 277 eggs, only 29 embryos developed, and only one sheep was born. She lived only six and a half years old, but gave birth to six healthy lambs. In 2003, Dolly had to be put to sleep: the animal suffered from the disease of the lungs and arthritis.
Copycat: Second life of pets
After Dolly, cloning went beyond the framework of experimental laboratories, and in some countries it was put on a stream, turning into a profitable business. In 2001, in Texas University of Agriculture and Mechanical Engineering for the first time cloned the cat. It was called Copycat, or just CI. Four years later, South Korean scientists have created the world’s first copy of the dog – she has become African boosane.
In South Korea, clones serve at customs: these are Labradors-Retrievers with the most subtle silent
Today, a number of companies, cloning pets, offers services to people who lost their favorites. Share a ceremonial amount are ready as celebrities and ordinary citizens. Barbra Streisand paid $ 50,000 per clone of his dog, and a resident of Beijing Huang Yu parted from $ 35,000 to "return" a cat garlic. The latter first buried the cat, but then addressed the company Sinogene to get it a copy. To do this, it took 40 embryos and four cats, which made embryos. Only one pregnancy was successfully ended: the kitten was born in July 2019 and became the first homemade cat, cloned in China. True, despite the confirmed genetic identity, duplicate differs from the prototype: little garlic has brighter wool, another color of the eyes, and most importantly, there is no funny dark spin on the chin. Frustrated Juang Yuh, still with understanding, reacted to the fact that the possibilities of science are not endless, and Sinogene is now widely offered its services. According to her representative, several cat owners have already signed up for the procedure.
Other companies recreate domestic animals with unique features. In South Korea, clones serve at customs: these are Labradors-Retrievers with the most subtle silent. In the UAE, massively cloned fast and endless camels – champions of prestigious racing.
Mammoth mom: Rare and ancient
Reproductive cloning has more global goals – for example, the salvation of rare and disappearing animals. In 2001, a bull of Gaura was cloned in the USA, under threat of disappearance. Unfortunately, the calf-clone died shortly after birth. But the other dying mind was lucky more: in 2004, as a result of cloning, a young Bantonga – wild bull inhabiting in Indochier appeared. The kernels frozen in 1980 cells of Bantang have been introduced in egg cells of ordinary cows, having received 30 embryos. It was possible to endure two calves, but only one was born healthy.
In the UK, USA, Australia and India, allowed to recreate fabrics and organs for transplantation
Modern technologies plan to spread and for long-lasting animals. Most recently, Harvard Genetics began a bold experiment to create a copy of the mammoth. It’s not about cloning in its pure form, because the DNA of an ancient being is planning to log in to the eggs closest from living species – the mother for the mammoth should become elephant. It all started in 2013, when the remains of Mammoth, who deceased 43,000 years ago found in the Arctic. They are well preserved in permafrost: the fabrics were soft, blood even flowed. Experiments on the transplantation of Mammoth genes in the cell of the Cell of the African Elephant were successful and became the first step towards the revival of the disappeared giants. But to recreate dinosaurs will not work: they have extinct for too long ago, and DNA in their bone fabric is not preserved.
Artificial leather: organs in test tube
After in 2018, Chinese scientists have successfully cloned two Macabouledov, it became clear: the appearance of people-clones is the case of a near future. But today the cloning of the human body and biomaterials is prohibited almost all over the world – for ethical considerations and due to the imperfection of technologies. So far, only in the UK, USA, Australia and India, allowed to recreate fabrics and organs for transplantation. For this, embryonic stem cells are used, which can turn into almost any types of cells. Therapeutic cloning partly seems to be reproductive, but the process of the development of embryos is interrupted after 14 days. Then from embryonic stem cells in laboratory conditions are grown by material to replace the affected tissues, which is not rejected by the immune system during transplantation. For example, in the UK, so create artificial skin, and in the USA – urinary bubbles. In the future stem cells and their analogs plan to use in the treatment of blindness, complications after strokes, Parkinson and Alzheimer’s diseases. Looks like a cloning future. Although many do not like it.
