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being, a mutant (virus / bacteria / gene) has arisen, unnoticed and unfeared. The new virus multiplies and invades the human body.
The by-now vastly narrowed gene pool of human beings (everyone similarly "engineered") has no means of dealing with so sudden a
(mistake / flaw / threat). Perhaps one of those mysterious genes that was weeded out of the human (species / kind / sort) could have
saved a few people from this plague, but for bioengineering.
T a s k T w o. Read the article and define which paragraph (1, 2, 3, 4, 5) each statement (A, B, C, D, E) refers to.
A. The new technology produced human insulin.
B. There are many opponents to the technology.
C. Transgenic organisms are applied in many spheres of life.
D. The new method caused fears in scientific and public circles.
E. A GMO is a method of studying basic biological processes and creating new cells.
1. A genetically modified organism (GMO) or genetically engineered organism (GEO) is an
organism
whose
genetic
material has been
altered
using
genetic engineering
techniques. These techniques are generally known as
recombinant DNA
technology. With this technology, DNA
molecules
from different sources are combined into one molecule to create a new set of
genes
. This DNA is then transferred into an organism and causes the organism to acquire modified or novel traits. The term
"genetically modified organism" does not always imply, but can include, targeted insertions of genes from one into another
species
.
For example, a gene from a jellyfish, encoding a
fluorescent
protein called
GFP
, can be physically linked and thus co-expressed with
mammalian genes to identify the location of the protein encoded by the GFP-tagged gene in the mammalian cell. These and other
methods are useful and indispensable tools for
biologists
in many areas of research, including those that study the mechanisms of
human and other diseases or fundamental biological processes in
eukaryotic
or
prokaryotic
cells.
2. The general principle of producing a GMO is to add a lot of genetic material into an organism's
genome
to generate new
traits
–
Genetic engineering
– was made possible through a series of scientific advances including the discovery of
DNA
and the
creation of the first recombinant
bacteria
in 1973. This led to concerns in the scientific community about potential risks from genetic
engineering which have been thoroughly discussed at the
Asilomar Conference
in Pacific Grove, California.
3. The recommendations laid out from this meeting were that government oversight of recombinant DNA research should be
established until the technology was deemed safe.
Herbert Boyer
then founded the first company to use recombinant DNA
technology,
Genentech
, and in 1978 the company announced the creation of an
E. coli
strain producing the human protein
insulin
.
4. In 1986, field tests of bacteria genetically engineered to protect plants from frost damage (
ice-minus bacteria
) at a small
biotechnology company called Advanced Genetic Sciences of
Oakland
,
California
, were repeatedly delayed by opponents of
biotechnology. In the same year, a proposed field test of a microbe genetically engineered for a pest resistance protein by
Monsanto
was dropped.
5. Examples of GMOs are highly diverse, and include transgenic (genetically modified by recombinant DNA methods)
animals
such as
mice
, fish,
transgenic plants
, or various
microbes
, such as fungi and
bacteria
. The generation and use of GMOs has many
reasons, chief among them are their use in research that addresses fundamental or applied questions in biology or medicine, for the
production of
pharmaceuticals
and industrial enzymes, and for direct, and often controversial, applications aimed at improving human
health (e.g.,
gene therapy
) or agriculture (e.g.,
golden rice
).
E x e r c i s e O n e
. Read the article and choose the best beginning phrase from the given below to fill each of the gaps.
A. For instance, the bacteria;
B. In addition to bacteria;
C. Bacteria were the first organisms;
D. Genetically modified bacteria.
Transgenic microbes
1. _____ to be modified in the laboratory, due to their simple genetics. These organisms are now used in a variety of tasks, and
are particularly important in producing large amounts of pure human
proteins
for use in medicine.
2. _____ are used to produce the protein
insulin
, to treat
diabetes
. Similar bacteria have been used to produce
clotting factors
to
treat
haemophilia
, and human
growth hormone
to treat various forms of
dwarfism
. These recombinant proteins are much safer than
the products they replaced, since the older products were purified from cadavers and could transmit diseases. Indeed the human-
derived proteins caused many cases of
AIDS
and
hepatitis C
in haemophilliacs and
Creutzfeldt-Jakob disease
from human growth
hormone.
3. _____ being used for producing proteins, genetically modified viruses allow
gene therapy
. Gene therapy is a relatively new
idea in medicine. A virus reproduces by injecting its own genetic material into an existing cell. That cell then follows the instructions
in this genetic material and produces more viruses. In medicine this process is adapted to deliver a gene that could cure disease into
human cells. Although gene therapy is still relatively new, it has had some successes. It has been used to treat
genetic disorders
such
as
severe combined immunodeficiency
, and treatments are being developed for a range of other incurable diseases, such as
cystic
fibrosis
,
sickle cell anemia
, and
muscular dystrophy
.
4. _____ in your mouth which causes tooth decay is called Streptococcus mutans. This bacteria eats left over sugars in your
mouth and produces acid that eats away tooth enamel and causes cavities. Scientists have recently modified Streptococcus mutans to
produce ethanol. This transgenic bacterium, if properly colonized in a person's mouth, could possibly eliminate cavities and other
tooth related issues. Transgenic microbes have also been used in recent research to kill or hinder tumors, and fight
Crohn's disease
.
Genetically modified bacteria is also used in some soils to facilitate crop growth, and can also produce chemicals which are toxic to
crop pests.
E x e r c i s e T w o
. Read the article below and choose the best word to fill each gap.
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