The Use of DNA to Treat Disease
In recent years there have been great advances in medical science.
Scientists believe that a gene can be transplanted into humans who
suffer from severe diseases that are life threatening. These gene
transplants could perhaps cure diseases for which no effective
treatment now exists. This treatment is called gene therapy, one
method in a series of genetic techniques called genetic engineering.
Many benefits can be seen in the future if this research is allowed to
continue, however, concerns about how gene therapy could effect humans
in the future and the ethics involved with possible misuse of the
techniques could hinder this vital research.
The human body is made up of many trillions of cells. Inside each cell
is information that tells the cell what to do and how to work. This
information is contained in genes, which are made up of a chemical
called DNA. Through small differences in the DNA, information is coded
and stored. All the activities that a cell does, begin with reading
part of the information that is stored in the DNA of the genes.
There are approximately one hundred thousand genes in each human body
cell. Although the genes are the same in every cell, each type of cell
reads only certain genes. In this way a muscle cell looks and works
differently from a skin or liver cell.
There are two major types of cell in the human body, somatic
(non-reproductive) cells and germ line (reproductive) cells. Most
cells in the body are somatic. These cells provide all the body
structures and perform all the functions except for passing the
genetic information onto the offspring. Germ cells include eggs in
women and sperm in men, the information in these cells will be passed
onto the children. The information in somatic cells will not be passed
on to the next generation.
If the DNA of a particular gene contains mistakes then the gene may
not function properly. Sometimes the mistake will not have serious
effects on the body’s health, but other times it will cause a severe
genetic disease. Examples of this are cystic fibrosis, sickle cell
anemia and hemophilia. Hemophilia, for instance, is caused by a
malfunction in the gene that makes the blood clot. As further research
into human genetics is carried out it is becoming clear that other
diseases such as diabetes, cancer, heart disease and some manic
depressive illnesses also result from faulty DNA information.
For some of these genetic diseases, there are effective therapies that
do exist. Drugs, blood transfusions, changes in diet or
transplantation of organs can often help to compensate for the
incorrect information from the malfunctioning gene, e.g. a clotting
factor can be introduced to help people suffering with hemophilia.
Human gene therapy is another approach to the treatment of...