Article #1
Words to know
1. modify = to change
2. genes = controls our inherited traits, determining everything about us
3. genome = our complete set of genes
4. cystic fibrosis = a genetic diseases that affects the respiratory system
5. vector = the process by which a virus gets around the body
6. eugenic = improved genes
What is Genetic Engineering?
Genetic engineering, also called genetic modification, is the human manipulation of an organism's genetic
material in a way that does not occur under natural conditions. The first organisms genetically engineered were
bacteria in 1973 and then mice in 1974; genetically modified food has been sold since 1994.
Pros of Genetic Engineering in Humans:
To make disease a thing of the past
Most people on the planet die of disease or have family members that do. Very few of us will just pop
up to bed one night and gently close our eyes for the last time. Our genomes are not as robust as we would like
them to be and genetic mutations either directly cause a disease such as Cystic fibrosis, or they contribute to it
greatly. In the case of some conditions such as heart disease, genetic mutations can make our bodies more
susceptible to attack from viruses or our own immune system. If the full benefits of gene therapy are ever
realized we can replace the “dud” genes with correctly functioning copies.
To extend life spans
Having enjoyed life, most of us want to cling on to it for as long as possible. The genetic engineering of
humans has the potential to greatly increase our life spans. Some estimates reckon that 100-150 years could be
the norm. Of course, gene therapy for a fatal condition will increase the lifespan of the patient, but we're also
talking about genetic modifications of healthy people to give them a longer life. Once we fully understand the
genetics of ageing it may be possible to slow down or reverse some of the cellular mechanisms that lead to our
decline.
Better pharmaceuticals
The knowledge gained by working out genetic solutions for the above could help with the design of
better pharmaceutical products that are able to target specifically genetic mutations in each individual.
The Cons of Human Genetic Engineering
There's a big question mark over safety
There are risks associated with getting genes into a human body and having them carry out the desired
function. Some genes are carried in on viral vectors and these bugs have been altered so as not to infect a patient
with a disease. However, a small number of gene therapy trials have resulted in the deaths of some subjects.
Also, we simply do not know long term the potential consequences of altering genes. The human
genome and our whole bodies are a maze of complicated biological signals, pathways and interrelationships. A
positive change upstream could cause a negative effect downstream.
Genetic diversity
If we were all to undergo genetic modification would this limit our genetic diversity? Could there be a
danger that our gene pool diminishes and that as a population we become more susceptible to being wiped out
by a hitherto unknown disease threat?
A Slippery Slope? Ethics of Human Genetic Engineering
To say that genetic engineering has attracted some controversy would be an understatement. There are
many cries that scientists are 'playing God' and that it will lead to a two-tier society - the genetically haves and
the have-nots. Having said that, genetic engineering does hold the potential that parents could (if the technology
worked) assemble their kids genetically, to be smarter, to be more athletic or have a particular hair or eye color.
Though it's rather fanciful to suggest that intelligence could be improved by the substitution of a gene, it
may be found that there are several genes that are more commonly expressed in the genomes of intelligent
people than those with more limited intellectual capacity. It is this genetic engineering of humans that so
frightens people- that we could somehow design the human race. Though, some people point out other potential
benefits. What if it turned out that there were sets of genes that were commonly expressed in criminals - could
we tackle crime by weeding out those genes?
The technology is nowhere near there yet. In the United Kingdome, in January 2009, a mother gave
birth to a girl whose embryo had been selected to be free from a genetic form of breast cancer. Some see this
as a slippery slope towards a eugenic future; others view it as a valuable use of genetic engineering to
prevent disease from striking someone down.
Answer the questions in the spaces provided below them.
1. What are two positive aspects of genetic modification that the author provides in the article “What is
Genetic Engineering”? Provide evidence to support your answer.
2. What are two negative aspects of genetic modification that the author provides in the article “What is
Genetic Engineering”? Provide evidence to support your answer.
3. The author uses different types of evidence to support both the positive and negative claims regarding
genetic modification. Identify two types of evidence used by the author and give an example of each.
4. What is the author’s purpose of this article?
5. What is the text structure of this article? Identify the context clues for the text structure?