Transcript Introduction to Biotechnology & Genetic Engineering

Introduction to Biotechnology
& Genetic Engineering
Introduction to Biotechnology &
Genetic Engineering
• Biotechnology - humans manipulate how
traits pass on – either through breeding or
through DNA manipulation
Biotechnology - Then
• Humans have been manipulating
organisms and their genes for years,
through:
– Selective breeding
– Hybridization
– Inbreeding
– Increasing mutations
Selective Breeding
• Allowing only those organisms with
desired characteristics to produce the next
generation
• Pass desired traits onto next generation
• Done with domestic organisms
– Ex. Breeding cows that produce the most
milk
Hybridization
• Crossing of dissimilar individuals to bring
together the best of both organisms
• Offspring are often hardier than parents
– Ex. Can withstand more extreme
temperatures, more endurance, need less
water, etc.
Some Hybrid Examples
A Tigon – a cross between a male
tiger and a female lion.
Some Hybrid Examples
A Liger – a
cross
between a
male lion
and a female
tiger.
Some Hybrid Examples
A Zorse – a
cross
between a
male zebra
and a female
horse.
Some Hybrid Examples
A Mule – a cross between a male
donkey and a female horse.
Some Hybrid Examples
A Beefalo – a cross between a
buffalo/bison and cattle.
Some Hybrid Examples
A leopon – a leopard and a lion
cross.
Some Hybrid Examples
Some Hybrid Examples
A Cama – a cross between a llama
and a camel.
Some Hybrid Examples
Labradoodles – a cross between
labradors and poodles.
Some Hybrid Examples
Goldendoodles – a cross between
golden retrievers and poodles.
Some Hybrid Examples
Many of the wide variations in the
colors of flowers is due to
hybridization.
Inbreeding
• Continued breeding of individuals with
similar characteristics
• Ensures that the characteristics that make
each breed unique are preserved
• Done with dogs, cats, horses, etc
• Does have risk for exposing genetic
defects
– Ex. Hip problems in German Shepherds, and
many large dog breeds
Increasing Variation
• Breeders can increase the genetic
variation in a population by incorporating
mutations
– Ex. Color variations in dogs/cats/horses
• Mutations are the ultimate source of
genetic variability
Biotechnology - Now
• Biotechnology today means the use of
DNA technology:
– Recombinant DNA for genetic engineering
– Transferring genes from one organism to
another (creating transgenic organisms)
Recombinant DNA Technology
• Recombinant DNA is constructed when
scientists combine pieces of DNA from two
different sources to form a single DNA molecule.
• Recombinant DNA technology is widely used in
genetic engineering, the direct manipulation of
genes for practical purposes.
Transgenic Organisms
• A transgenic organism contains a gene from
another organism, typically of another species.
• Transgenic organisms have been used to
produce:
•
human insulin in large quantities (Humulin – made by
genetically modified bacteria)
• human growth hormone (HGH – for some people,
without HGH, dwarfism can result)
• the hormone erythropoietin (EPO), which stimulates
production of red blood cells
• vaccines
Genetically Modified Food (GM
Foods)
• Today, DNA technology is quickly replacing traditional
breeding programs – MANY of our foods are genetically
modified in some way
• Transgenic Plants - Uses
– Corn has been genetically modified to resist insect
infestation
– Strawberry plants produce bacterial proteins that act as a
natural antifreeze
– Potatoes and rice have been modified to produce harmless
proteins derived from the cholera bacterium and may one
day serve as edible vaccines.
Transgenic Animals
• Transgenic Animals - Uses
– A transgenic pig has been produced that carries a gene for
human hemoglobin that could be used in transfusions
– Growth hormone gene in livestock to grow faster and
produce less fatty meat
– May soon produce supply of human proteins in milk
– In 2006, genetically modified pigs carried roundworm genes
that produce proteins that convert less healthy fatty acids to
omega-3 fatty acids.
– However, unlike transgenic plants, no transgenic animals are
yet sold as food.