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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.
