Gene Therapy

Over the last few years, I have learnt a lot about Gene Therapy and Genetic Engineering as part of my everyday work.  

Today in this post, I am going to briefly explain what it is and try to break down the ethical issues. 

Genes are chemical reactions in cells that make it grow and function and ultimately determine the growth and function of an organism. 
An organism inherits some genes from each parent and the parents pass on certain traits to their offspring.

Gene therapy and genetic engineering are two closely related technologies that involve altering the genetic material of organisms.  

Gene therapy seeks to alter genes to correct genetic defects and thus prevent or cure genetic diseases.  Genetic engineering aims to modify the genes to enhance the capabilities of the organism beyond what is normal.

Ethical controversy surrounds use of both of these technologies in plants, nonhuman animals, and humans.  Currently, the biggest issue is with genetic engineering, I wonder whether you could alter human genes to make it possible for a person to be able to outperform the greatest Olympic athletes or to become a lot smarter than Einstein.

Genetic engineering is meant in a very broad sense and includes any intentional genetic alteration, so it includes gene therapy.
Genetic engineering is used for the kind of alteration that aims at enhancement rather than therapy.  Gene therapy is used for efforts to bring people up to normal standard and genetic engineering or enhancement genetic engineering for efforts to enhance people’s capabilities beyond normal.

Most of the cells in our bodies are somatic cells that make up our organs like the skin, liver, heart, lungs, etc.,  these cells vary from one another.  Changing the genetic material in these cells is not passed along to a person’s offspring.  Reproductive cells are sperm cells, egg cells, and cells from very early embryos.  Changes in the genetic make-up of reproductive cells would be passed along to the person’s offspring.  These cell changes will result in different genetics in the offspring’s somatic cells because the genetic makeup of somatic cells is directly linked to that of the germ cells from which they are derived.

When you make changes or you alter genes, you really have to think, firstly what change is being made? Secondly, how is the change going to be incorporated in all the other cells that must be changed to achieve the desired effect.

There are several options for the kind of changes that can be made to a gene;

DNA in the gene could be replaced by other DNA from outside (called homologous replacement). 
The gene could be forced to mutate (change its structure, which is selective reverse mutation) 
A gene could just be added.
A chemical spray could be used to turn off a gene and prevent it from acting.

There are also several options for how to spread the genetic change to all the cells that need to be changed;
If the altered cell is a reproductive cell, then a few such cells could be changed and the change would reach the other somatic cells as those somatic cells were created as the organism develops.
If the change were made to a somatic cell, changing all the other relevant somatic cells individually like the first would be impractical due to the sheer number of such cells. 
The cells of a major organ such as the heart or liver are too numerous to change one-by-one.  Instead, to reach such somatic cells a common approach is to use a carrier, or vector, which is a molecule or organism.  A virus, for example, could be used as a vector.  The virus would be an innocuous one or changed so as not to cause disease.  It would be injected with the genetic material and then as it reproduces and infects the target cells it would introduce the new genetic material.  It would need to be a very specific virus that would infect heart cells, for instance, without infecting and changing all the other cells of the body.  Fat particles and chemicals have also been used as vectors because they can penetrate the cell membrane and move into the cell nucleus with the new genetic material.

Arguments in Favor

Gene therapy is viewed by many as morally unobjectionable, though caution is urged.  The main arguments in its favor are that it offers the potential to cure some diseases or disorders in those who have the disease or disorder and it can prevent diseases in those whose genes are predisposed to such problems.  If done on reproductive cells, gene therapy could keep children from carrying such genes, especially in the cases of unfavorable genetic diseases and disorders,  that children would get from their patients.

Genetic engineering to enhance organisms has already been used extensively in agriculture, primarily in genetically modified crops (GMO --genetically modified organisms). 
Some crops and stock animals have been engineered so they are resistant to herbicides and pesticides, which means farmers can then use those chemicals to control weeds and insects on those crops without risking harming those particular plants. 

In the future genetic enhancement could be used to create crops with greater yields of nutritional value and selective breeding of farm stock, race horses, and show animals.

Genetically engineered bacteria and other microorganisms are currently used to produce human insulin, human growth hormone, a protein used in blood clotting, and other pharmaceuticals, and I have been told that the number of such compounds could increase in the very near future.

The arguement for enhancing humans is that it could make life better in significant ways by enhancing certain characteristics of people. 
As humans we value intelligence, beauty, strength, endurance, and certain personality characteristics and behavioural tendencies, and if these traits were found to be due to a genetic component, we could enhance people by giving them such features. 
Advocates of genetic engineering point out that many people try to improve themselves in these ways already – by diet, exercise, education, cosmetics, and even plastic surgery.  People try to do these things for themselves, and parents try to provide these things for their children. 
Humans already pick a mate on the basis of the possibility of providing desirable children.  We therefore think nothing is wrong with choosing a mate whom we hope might provide smart, attractive kids over some other mate who would provide less desirable children.  Choosing a mate for the type of kids one might get is a matter of basic reproductive freedom and we have the freedom to pick the best genes we can for our children.

Arguments Against Gene Therapy

Three arguments exist regarding gene therapy, firstly it is technically too dangerous, secondly that it discriminates or invites discrimination against people with disabilities, and thirdly, that it may be becoming increasingly irrelevant in some cases.

Some recent attempts at gene therapy in clinical trials have made headlines because of the tragic deaths of some of the people participating in the trials.  It is not fully known to what extent this was due to the gene therapy itself, as opposed to pre-existing conditions or research techniques, but in the light of these events critics have called for a stop to gene therapy until more research has been completed. 
I think we simply do not know enough about how gene therapy works and what could go wrong. 
Specific worries for me are around the vectors that may deliver the DNA to cells in the body rather than the target cells, with unforeseen results viruses as vectors may not be as innocuous as assumed and may cause disease, adding new genes to a nucleus does not guarantee they will go where desired, with potentially disastrous results if they insert in the wrong place.  If the changes are not integrated with other DNA already in the nucleus, the changes may not carry over to new cells and the person may have to undergo more therapy later.  Changing reproductive cells may cause events not seen until years later and undesirable effects may have already been passed on to the patient’s children. 
People who are physically, mentally, or emotionally impaired are so as the result of genetic factors they have inherited.  Such impairments result in disablement in today's society.  By removing genetic disorders, and resulting impairment, it is true that gene therapy could contribute to removing one of the sources of discrimination and inequality in society,  But people impaired through genetic factors need to be treated and made normal. 
Gene therapy is seen as a form of discrimination against impaired people and people with disabilities.

Gene therapy on reproductive cells may in some cases already be superceded by in-vitro fertilization and selection of embryos.  If a genetic disorder is such that can be detected in an early embryo, and not all embryos from the parent couple would have it, then parents would produce multiple embryos through in-vitro fertilization and implant only those free from the disorder. 
In such a case gene therapy would be unnecessary and irrelevant.

Against Genetic Engineering

The most concern comes from implications and problems with genetic engineering. 
Firstly, not enough is known and there may therefore be unforeseen consequences.  I have seen so many cartoons of freakish creatures that might result from experiments gone wrong.

Genetic engineering is against natural order.  God, has created a set of genes for human beings that are either what we should have or that offer us the best survival value.  It is against what God or nature intended to tinker with this genetic code, as in gene therapy, but to create new kinds of beings. 
Genetic engineering is dehumanising because it will create nonhuman, alienated creatures. 
Genetic engineering is a version of eugenics, this is the view that we should improve the genetics of the human race; selective breeding, forced sterilisation of defectives and undesirables (people with genetic disorders or undesirable characteristics or traits, people with disabilities, people of other races, people of other ethnic groups, homosexuals), and euthanasia of such populations.  These practices are now largely viewed as morally abhorrent.  Critics of genetic engineering see it as an attempt at eugenics through technology.

As you read this, Gene therapy is becoming a reality.  Genetic engineering for enhancement is still a long, long way off.
This is a topic, I have a lot of interest in and have attended countless talks by Pharma companies. 
Plenty of debate is sure to occur over both issues over the next few years.