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Saturday, February 14, 2004

Ones of a Kind


Dr. Lester CN Simon

It is a truth, universally accepted, that sickness and health are attended unequally by luck, money, common sense and good governance. Doctors struggle to square this trapezium. We try to keep up with dazzling advances in medicine and to fulfil the needs of our patients.

So what’s the fuss about the milestone news on cloning and stem cells? Let’s start with fertilization. This is the process in which genetic material in the sperm from the male unites with genetic material in the egg from the female.

Except for egg cells in the ovary in females and sperm cells in the testis in males, all other cells in humans have 46 genetic materials. Egg cells and sperm cells contain only 23 genetic materials. When the egg and the sperm combine during fertilization, the offspring will then have the full complement of 46 genetic materials.

Cloning is an attempt to create cells that are genetically identical to an original cell. This is a radical departure from natural fertilization in which the offspring is not genetically identical to the mother or the father but rather it is a genetic composite of both parents.

In cloning, the egg is manipulated outside the body before the sperm is introduced. The sperm is not used at all. The 23 genetic materials in the egg are removed. These are then replaced by 46 genetic materials from other cells which already have the ready-made 46 genetic materials. The egg does not realize that the new 46 genetic materials did not come from the natural combination of 23 from the egg and 23 from the sperm.

After this false fertilization by manually inserting into the empty egg, the ready-made 46 genetic materials, special chemicals called growth factors and others are added. The egg is fooled into growing and developing as if a normal egg had been fertilized by the sperm.

With nuff respect to the women of POWA in particular and to all women in general, the indispensable role of the egg should be underscored. After removing the 23 genetic materials from the egg, the egg is still essential for the implantation of the ready-made 46 genetic materials from another cell. In effect, a female’s empty egg can be falsely fertilized by the 46 genetic materials in cells from herself, another female or a male. The male’s sperm cannot perform this receptive, nurturing function.

In the landmark study just published, the ready-made 46 genetic materials were provided by the same female that provided the egg. The researchers also tried to clone male cells by using cells from the ear lobe. They were unsuccessful. With all respect to the eminent scientists, a woman would have told them that since men just don’t listen, they should have taken the 46 genetic materials from some other part of the male’s anatomy! Any suggestions?

Stem cells refer to cells that give rise to other cells. They do this after fertilization, throughout pregnancy and for our entire life. All types of cells in the body are derived from stem cells. These include blood forming cells, heart cells, nerve cells, etc. Stems cells that are made soon after fertilization are more potent than those made as we grow older.

In many diseases, the underlying problem is a fault with the stem cell and this fault is passed on to the regular cells, which become dysfunctional. Such diseases include sickle cell disease, diabetes, heart disease, cancer and brain diseases, among others.

The value of manufacturing stem cells is that it is hoped that stem cells may one day be injected into patients to replace the deranged stem cell that caused the disease. This is referred to as therapeutic cloning since the idea is to clone cells only to harvest the potent stem cells early for the treatment of diseases. Alternatively, reproductive cloning refers to cloning an animal or a human being by allowing the cloning process to go all the way after implanting the falsely fertilized egg in a woman’s uterus.

There are many ethical and legal issues about cloning. Regarding reproductive cloning, take a look in the mirror. You should like what you see but do you really think we can tolerate another one exactly like you in this world? When in a fit of rage you tell your “what-ever” daughter that you wish she will have children just like her, do you really want your wish granted?

Concerning therapeutic cloning, it is a truth, locally accepted, that we are struggling to walk like moko jumbie to see a new hospital on the hill while we are crawling like ground lizard to barely see to Holberton hospital on the plain.

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