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Chapter 97: Misunderstanding Cloning

In the end, after the physical examination and bone age test, only thirty-three of the fifty elderly people met the requirements of the experiment.

The remaining seventeen who did not fit the bill were naturally sent back.

It was impressive that Gorob Village could come up with so many people above fifty years old. Apparently, for the village chief to get the numbers, he had rushed over to the neighboring villages himself to negotiate for more people.

Elderly people were scarce because of the lack of medical care. It was still alright in the city, but in the villages, there were not many who could live beyond the age of fifty.

Namibian officials had calculated the statistics. In this country, more than ten percent of the children were orphans because the parents of these children had died of AIDS shortly after giving birth.

In Namibia, the national population was only 2.58 million but the HIV infection rate had reached 21.3%. This meant that one in five people of this country was HIV-positive.

However, the fortunate thing was, the HIV infection rate in Namibia was not considered too high. It was far below Botswana’s 37.3%, Swaziland’s 38.8%, and Lesotho’s 28.9%.

Africa was world-famous for two things. One was diamonds and the other was AIDS.

Ignoring the dissatisfaction of the Gorob villagers, Chen Chen made the thirty-three people take a bath, then arranged for them to live in the basement. They were well-fed but their area of movement was restricted.

At the same time, in the laboratory, Chen Chen had recruited a group of experienced assistants and started the cloning process for the embryos of these elderly people.

In terms of specific operations, Chen Chen used a more advanced three-dimensional polarization spindle imaging system. After positioning the egg cell nucleus, he used a laser to punch a hole in the zona pellucida, then removed the nucleus without damaging the egg cell. Only then was he able to use the micromanipulator to implant the somatic cell nucleus of the elderly.

However, it was too bad that the techniques of these assistants could not compare to Chen Chen’s. They failed several times in the middle as well as during the process of using electric current and chemical induction. In the end, Chen Chen’s guidance was necessary to complete all the cloned embryos.

Following that, the cloned embryos needed 14 days of growth to reach the blastocyst stage, after which the embryonic stem cells within would be extracted.

International opposition against human embryo cloning was mostly due to this step. To some people, killing these fertilized eggs was equivalent to killing people, which was ethically unacceptable.

Even so, fortunately, these objections did not hinder the study of cloned embryos. As of now, the technology of embryonic stem cell cloning in various countries was still making great strides.

By controlling the growth environment and manipulating the expression of specific genes after the embryonic stem cells were extracted, these stem cells could be differentiated into the required hematopoietic stem cells and mesenchymal stem cells.

The stem cells cloned with this method had almost the same genes as those of the elderly, so there would not be any rejection. Plus, these were young, healthy stem cells.

After the elederly people had gone through chemotherapy and radiotherapy, the stem cells would be implanted into their bodies to replace the stem cells that had aged long ago.

Once these young hematopoietic and mesenchymal stem cells returned to the bone marrow, they would swiftly differentiate into blood cells, muscle cells, liver cells, osteoblasts, fat cells, chondrocytes, stroma, and other human cells, repairing and improving the damages of aging.

This was the function of stem cells.

However, for some time, academia had been caught up in a massive misunderstanding, which arose from the earliest cloning of the sheep, Dolly —

Everyone knew that the cloned sheep Dolly was the world’s earliest artificially cloned animal. Before Dolly was born, its cell donor was a white-faced Finnish Dorset sheep.

The experimenter had extracted mammary gland cells from this sheep, then took out the nucleus. Thus, Dolly was cloned.

In other words, Dolly’s genes were basically the same as this white-faced Dorset sheep.

This white-faced Finnish Dorset sheep was 6 years old when its mammary gland cells were extracted.

However, after the cloned sheep Dolly was born, it was discovered that Dolly’s telomeres were shorter than other sheep of the same age.

Not only that but Dolly also showed signs of premature aging when she was 6 years old. Although she was well taken care of, Dolly eventually died.

In the same year, the white-faced Finnish Dorset sheep, the donor of the cloned sheep Dolly, died at the ripe old age of twelve.

In biology’s research on lifespan and aging, the more mainstream theories were “telomere theory” and “free radical theory”, both of which had not been thoroughly confirmed. Still, if telomeres were the key factor affecting lifespan, then the death of the cloned sheep Dolly seemed to support this theory.

The nucleus donor for Dolly was a six-year-old sheep. Therefore, although Dolly was newly born, her telomere length had been worn down to only six years of life? Thus, she would die at the same time as the donor, six years later?

Back then, this misunderstanding had affected the entire academia, casting a shadow over cloning technology.

This was because, if this conclusion was accurate, then most treatments developed from cloning technology were futile. No matter what the cloning process was, the length of the telomeres was fixed and could never be altered...

This misunderstanding even influenced science fiction after 2000, resulting in works that had clones who were collectively cursed with the defect of short lifespans.

Fortunately, at the end of 2019, this misunderstanding was finally unraveled —

In November 2019, Professor Li’s team of the Key Laboratory of Animal Reproductive Regulation and Breeding in Mainland China had reached a decisive conclusion after studying the telomeres of cloned animals.

After years of research, Professor Li’s team discovered that cloned embryos would undergo telomere reprogramming during the activation of the zygotic genome. Regardless of the telomere length of the donor cell, the reprogramming process would restore the original length, which was the length of the donor!

Not only that, but Professor Li also discovered that the length of the telomeres was related to the development of the cloned embryos.

During the cloning process, the telomeres of cloned embryos with normal development would undergo a remarkable recovery while for cloned embryos with abnormal development, the telomeres would not recover and were shortened.

In addition, Professor Li also found that, in the process of culturing cloned embryos, adding some small molecules such as trichomycin A, sodium butyrate, melatonin, and so on, could effectively increase the reprogramming efficiency of the telomeres in low-oxygen conditions!

The result of this research was published in The FASEB Journal, which stood for the Federation of American Societies for Experimental Biology. The title of the paper was “Inhibiting repressive epigenetic modification promotes telomere rejuvenation in somatic cell reprogramming”.

With that, the misunderstanding that the lifespan of cloned animals was limited by the donors was completely debunked.

As for why the cloned sheep Dolly had premature aging and why her telomere length was insufficient? Well, people would find their own ways to justify that.

While Chen Chen was cultivating the cloned embryos of these elders in the laboratory, Dlamini finally sent over the people on the name list.

This time, Dlamini had sent a total of thirty people, all of whom were the cream of the crop. Even a trump card like Cheng Cao would seem rather unassuming among them.

As long as Chen Chen could subdue these wolfish mercenaries, the foundation for establishing a rapid reaction force in the future would be completely ready.

Chen Chen’s goal was to build a private armed force, capable of global precision strikes, in the next few years. Its main purpose would be to protect the company’s property around the world and destroy any evidence that would damage the company.