Transcript Biotechnology

Biotechnology
Making the products you buy. . .
better?
Historical Technologies:
Applied Genetics
• Manipulation of the hereditary characteristics
of an organism to improve or create specific
traits in offspring
– e.g., selective breeding, hybridization
Historical Technologies:
Applied Genetics
• Selective breeding → Allowing only those
individuals with the desired traits to reproduce
Historical Technologies:
Applied Genetics
• Hybridization → crossing different
individuals to bring together the best traits of
both organisms
– Produces hybrid offspring that are often hardier
than the parents
e.g., commercial chickens
X
White Rock
Chicken:
Grows quickly
White Cornish
Chicken:
Grows large
Commercial chicken:
Grows to a large full
size in only 6 weeks
Modern Technologies:
Genetic Engineering
• Altering an organism’s
genetic code (DNA) to get it to
express desired traits
http://images.google.com/imgres?imgurl=http://www.peaceproject.com/graphics/dvds/larger/DVD51.jpg&imgrefurl=http://www.p
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e.g., Bt
corn
• Bacillus thuringiensis (Bt): a bacterium that
produces a caterpillar toxin
• The gene for this toxin has been inserted into
this corn’s genome, which causes it to produce
the toxin
e.g., spider silk
• A spider’s silk-making
gene has been inserted
into a goat, which then
produces silk in its milk
http://www.chm.bris.ac.uk/motm/spider/goat.jpg
http://www.kevhopgood.co.uk/New%20Stuff/Spider-Goat.jpg
http://rockgardn.easystorecreator.com/images/imag
e.g., golden rice
• Daffodil genes for making
beta-carotene are inserted
into the genome of rice
http://www.jewishworldreview.com/toons/varvel/biotech.protest.gif
http://www.bairesbiotec.org.ar/images/speake1.jpg
e.g., human insulin
• Previously, humans with
diabetes used insulin derived
from the pancreas of cows and
pigs (limited production)
• Today, most human insulin
comes from human insulinmaking genes transferred into
simple cells such as bacteria or
baker’s yeast (unlimited supply)
– Identical to insulin made by the
human pancreas
Recombinant DNA in bacteria
• Recombinant DNA →
taking a piece of one DNA
and combining it with
another strand of DNA
• Often, fast-growing singlecelled organisms are used
– e.g., bacteria
• A piece of DNA that codes for
a protein we want more of
(e.g., human insulin) is
spliced into the DNA of the
fast-growing organism
http://img.blogcu.com/uploads/kedicikkopekcik_insrton.jpg
Modern Technologies:
Genetic Engineering
• Gene therapy →
adding a corrected copy
of a gene to a person
with a mutated gene to
treat a disease
– e.g., Cystic Fibrosis
• Does NOT change the
person’s genetic code!
– Effect is temporary
Restriction Enzymes:
Enzymes that
cut DNA at
certain
sequences.
http://www.accessexcellence.org/RC/VL/GG/images/restriction.gif