Lives on earth in various forms and shapes have come about through very complex and convoluted processes. Single cell organisms like amoeba to multi-cellular organisms like plants and animals have progressed through millions of years of slow and painstaking developments of trials and errors, alterations, modifications and so forth, which are collectively called the evolutionary process. Eventually, when an organism emerges in some viable form, it is not the end of the process, it is only the beginning. It will go on for further refinement to a better, fitter form of life. It may, nonetheless, take a wrong evolutionary step and suffer the wrath of nature and be extinct. For every surviving form of life, there are hundreds of similar lives that had either failed to develop properly and gone extinct.
Life, particularly human life, comes into existence in a tortuous way. When a male sperm cell fertilises a female egg cell, the combined single cell, called the zygote, is formed. The sperm cell and the egg cell are the reproductive organ cells – each containing 23 chromosomes – when they combine, they make up a fully developed cell containing 46 chromosomes. It may be noted that not all sperm cells fertilise egg cells. What triggers this fertilisation is still a mystery; it may just be a draw of the luck. However, this single cell zygote keeps dividing by a process called cell division, as it moves along the Fallopian tube towards the uterus. The zygote contains all the genetic instructions inherited from the father and the mother. When it reaches the uterus in three to five days, the zygote becomes what is called a blastocyst or a ball of cells. The blastocyst consists of two parts: an outer cell mass that becomes part of placenta and an inner cell mass that becomes the human body.
A cell is the basic functional unit of life. A cell is surrounded by a cell membrane and within the membrane lies a blob of transparent dilute fluid, cytoplasm and within the cytoplasm lies the cell nucleus. The nucleus of human beings contains 46 chromosomes in 23 pairs. A chromosome consists of very long DNA helix on which thousands of genes are embedded. It was anticipated that the secrets of life are all hidden within these DNA molecules. The discovery of this secret is a fascinating story.
In the early 1940s, the Austrian physicist Erwin Schrodinger, one of the pioneers of quantum physics, wrote a very thoughtful science classics book called ‘What is Life?’. He maintained that there was no divine power or mysterious spirit that needed to animate life. He speculated that life force must come from within the body, probably embedded within the molecules of the body. Inspired by Schrodinger’s book, physicist Francis Crick teamed up with geneticist James Watson and Maurice Wilkins to study molecular biology and discovered the structure of the DNA molecule within the cell. They proposed that the DNA molecule has a double helix structure and the interlink between the base pairs of the double helix contains the codes necessary for life. For their discovery, the trio won Nobel Prize for medicine in 1962. The segments of the DNA molecule with specific instructions for particular actions are called the genes.
Thus, the cells with all the internal complexities and functions constitute the smallest unit of life. There are multitudes of cell types, but the basic structure is the same. The blastocyst formed out of zygotes contains embryonic stem cells. It is estimated that humans contain 40 trillion (40,000 billion) cells in a fully developed body.
The embryonic stem cells are extremely important as they contain all the genetic information of an individual, unmodified and unaltered. These embryonic stem cells are pluripotent stem cells, meaning they can divide into more stem cells or can change into any type of tissue cell like the blood cell, liver cell, skin cell, brain cell etc. Because of this ability and its unaltered state, embryonic stem cells are highly prized for medical research. But there are downsides too; the embryo has to be sacrificed to extract these cells and that raises serious ethical objections.
When embryonic stem cells mature, they become tissue-specific somatic cells tasked to produce body tissues and there are more than 200 types of tissue-cells in the body. Each of these cells contains the full genetic code, no matter where it finds itself, although all instructions to divide and grow are suppressed, except for this particular tissue. For example, blood cells are only responsible for generating blood, liver cells for liver, skin cells for skin etc, although each one has the full blue print for life. There are also non-embryonic stem cells, namely adult stem cells or induced pluripotent stem cells.
Medical research is going ahead using stem cells to cure humans from ailments like strokes, repair heart muscles following heart attack, cure neurological problems like Alzheimer’s disease, Parkinson’s disease etc. Stem cells can also be used to produce insulin to cure people with diabetes.
Stem cells can also be used to regenerate or repair organs such as nose, ear, lungs etc or limbs such as arms, legs etc. This aspect promises to have tremendous beneficial effects on soldiers who have lost their organs or limbs in battle fields. They can have their limbs repaired genetically or even have them newly grown in the laboratory. These are not pie in the sky aspirations. Already some organs such as hearts or lungs have been developed in the laboratories, but not in situ in primates or humans.
With such wide-ranging medical benefits against incurable and debilitating diseases and ailments, why then Western Countries are putting restrictions on the use of stem cells and particularly embryonic stem cells in medical research? It is due to the fact that from the cure of these diseases, it is a small step to modify human genome in such a way that artificially super humans can be produced. In other words, super human Frankensteins can be produced with all the attributes one desires. Thus, uncontrolled medical research can lead to Eugenics or make it a distinct possibility.
Before and during the second world war, Hitler and his Nazi party seriously considered developing a super Euro-Aryan race where people would not only be physically strong and intellectually superior, but also free from all genetic diseases. It may, however, be noted that this idea of Eugenics was not the original Nazi invention, it was imitated from a Californian company who had been working on it for quite a few years prior to 1930s.
When the cloned humans with edited and vetted genes are produced, what would be the fate of normal human beings born traditionally with male and female fertilisation with normal genetic make-up? Eugenics proposed that all those people who were deemed by the State to be racially inferior such as Jews, gypsies etc, as well as handicapped, genetically abnormal people etc were to be exterminated to make way for the superior human race! That Eugenics died with Hitler was a great blessing for human race.
Stem cell research with the specific purpose for curing diseases like diabetes, cancer, genetic disorders, neurological diseases like Parkinson’s, Alzheimer’s etc is the beneficial aspects. But this can go a little further and pave the way to dehumanize humans or even destroy humanity. It is a double-edged sword – use it carefully, otherwise risk it to destroy you.
One thing that this genetic manipulation has done or almost at the brink of doing is to make human immortality a reality. Although sheep, cattle etc. have been successfully cloned, but primates and human beings have not yet been cloned. It is primarily because the research and in-situ testing of cloning on humans are banned in almost everywhere in the world. But if that ban is removed, the technology can be developed in a short period of time. An adult stem cell is removed from a human being, its DNA is extracted and the cell is inserted in an egg cell and let it develop in the normal way and then a clone copy of the donor human being is going to come out! Of course, it is not as easy as said, but the technology is almost there to achieve it.
The implication of human cloning is enormous. A very rich man (or woman) at nearer the end of his (or her) life may decide to live on for ever. Of course, he himself cannot live for ever; as he will age, his body functions will deteriorate and his body will gradually decay. But what he can do is to donate his cells, particularly stem cells for future fertilisation. His stem cells may be deep frozen and, as per his instructions, they may be fertilised at the desired time and a human being will come out of the cloning process. That particular (rich) man is thus reborn; one can say he is reincarnated. That rich man can also in his Will transfer his wealth to the child (yet to be born) and when the cloned child is born, he is as wealthy as his predecessor. The boy will have all the body functions, body characteristics etc of the donor, but not his memory nor the characteristics derived from the memory. In other words, he will have a blank brain slate. He will have to learn everything afresh, go to schools, play games and develop his individuality, but with the exact replica of the body of the donor. Thus, this man can replicate himself over and over again and live for ever.
We are now at the threshold of genetic revivalism, for good or for bad. Gone are those days when we had to blindly believe in fictitious divine power creating life on earth (through Adam and Eve) and submit to religious edicts without any question! In reality, life evolved from the single cell amoeba to multi-cellular organism. Now science and technology have progressed sufficiently enough to create and recreate lives with any genetic make-up. But if we allow artificial genetic creation take over the natural evolutionary process, it would be a disaster of unparalleled proportions. We must resist that temptation at all costs.
- Dr A Rahman is an author and a columnist