Attempts to breed extinct or endangered animals have so far failed; The scientists plan to bring back to the world the hairy animal that became extinct about ten thousand years ago
In recent years, Japanese scientists have been trying to prove that reality surpasses all imagination, even if the imagination is that of writer Michael Creighton and Hollywood director Steven Spielberg, creators of "Jurassic Park". Using advanced technologies, they are trying to clone the hairy mammoth, which became extinct about ten thousand years ago.
Last month, scientists from two universities in Japan - Kinki and Tipu - managed to overcome the Russian bureaucracy, and received in their hands a sample of tissue taken a few years ago from one of the mammoths found in the tundra - the frozen steppe region of the Arctic Circle. But the road to cloning mammoths is long. Indeed, this is not the first time that scientists try to bring extinct species back to the world. Earlier they tried to clone the Tasmanian tiger, which became extinct 65 years ago, and the Moa, a bird that became extinct 400 years ago. These attempts failed.
Apparently, the attempt to bring extinct animal species back into the world is a worthy goal. Scientists focus on animals that seem to have disappeared from the world not due to natural selection, but because of humans. Since the cloning of Dolly the sheep in 1997, scientists believe that they have scientific tools in their hands that make it possible to bring extinct animals back to life. However, they also know that without complete and correct DNA of the mammoth they will find themselves at a dead end.
The solution: a fillet egg
The first option for returning the mammoth to the world is through the in vitro fertilization technique, and it requires the scientists to obtain a sperm cell from a male mammoth. For this they must locate a mammoth and extract sperm cells from its testicles. Because the mammoths found were buried for thousands of years in deep ice, scientists hope to find sperm cells that, after thawing, will be live sperm, containing a normal copy of the genetic cargo.
In that case, the scientists will take an unfertilized egg of an African elephant, considered the closest relative of the mammoth, and fertilize it with a sperm cell. After fertilization, the egg will be implanted in the womb of a surrogate filly. A female elephant will give birth to a hybrid son - half elephant and half hairy mammoth. After a few generations (probably about 50 years), the animal will contain 88% of the genetic load of the ancient mammoth. Those who want to use the in vitro fertilization method to bring the hairy mammoth back to life need not only mammoth sperm, but also the animal's egg, which is unlikely to be found.
Since finding a sperm is also not considered a reasonable possibility, the scientists concentrate on the second option - cloning. The researchers who created Dolly the sheep fused a cell taken from a sheep's udder wall with a sheep egg, from which the cell nucleus had been extracted. The nucleus of the udder cell took over the egg and determined the course of its development into an embryo, and finally into a lamb.
The Japanese scientists intend to imitate the process, but instead of a sheep they want to create a mammoth. For this they are looking for some tissue in the mammoth's body that contains cells "in excellent animal condition". If they find such a tissue, they will take the cell nucleus that contains the genetic load, fuse it with the egg of the fillet from which the nucleus was removed, and cause the egg to start dividing. At the end of the process, the fertilized embryo will be implanted in the uterus of a surrogate sow. This scenario is the scientists' rosy dream, since success means the birth of a living creature that is 100% mammoth.
