Basic idea is to copy a
useful gene from one
organism's chromosome into
the cells of another...
1) Useful gene is ''cut''
from one organism's
chromosome using
enzymes
EcoR1
2) Enzymes are then used
to cut another organism's
chromosome and the
insert the useful gene
''Glued'' together by Ligase
3) Scientists use
this method to do
all sorts of things
For example, the human
insulin gene can be
inserted into bacteria to
produce human insulin
Genes can be Transferred
into Animals and Plants
The same method can be used to
transfer useful genes into animals
and plants at the very early stages
of their development
This means they'll develop useful characteristics:
1) Genetically Modified
(GM) crops have had
their genes modified
e.g. to make them
resistant to viruses,
insects or herbicides
2) Sheep have been
genetically engineered to
produce substances, like
drugs, in their milk that
can treat human diseases
3) Genetic disorders
like cystic fibrosis are
caused by faulty genes.
Scientists are trying to
treat these disorders by
inserting working
genes into suffers. this
is called gene therapy.
Controversial
Topic
It is an exciting new area in science which
has the potential for solving many of our
problems (e.g. treating diseases, more
efficient food production etc.) but not
everyone thinks it's a great idea.
There are worries about long-term effects
of genetic engineering - that changing a
person's genes might accidentally create
unplanned problems, which could then be
passed on to future generations.
It's the same as GM Crops
- There Are Pros and Cons
1) Some people say that
growing GM crops will affect
number of weeds and
flowers (and so the
population of insects) that
live in and around the crops
- reducing farmland
biodiversity
2) Not everyone is convinced
that GM crops are safe. People
are worried they may develop
allergies to the food - although
there's probably no risk for this
than for eating usual foods.
3) A big concern is that
transplanted genes may
get out into the natural
environment
For example, the herbicide
resistance gene may get
picked up by weeds, creating
a new 'superweed' variety
4) On the plus side GM crops can
increase yield of crop, making more food.
5) People living in developing nations often lack
nutrients in their diet. GM crops could be
engineered to contain the nutrient that's missing.
For example, they're testing 'golden rice'
that contains beta-carotene - lack of this
substance can cause blindness
6) GM crops are already being grown elsewhere
in the world (not in UK) often without any problems