2. - Archeological evidence shows that humans
began cultivating plants and animals for food
about 10,000 years ago
- Specific organisms were bred to improve
future generations
- Simple form of applied genetics
4. Types of Controlled Breeding
1. Selective Breeding
Process of choosing a few individuals to serve as parents
for next generation
- Luther Burbank: Californian plant
breeder (early 1900s)
- responsible for 800 new plant varieties
Ex: seedless grape
Spineless cactus
Burbank potato
Daisies
- Corn: bred for 7000 years
- Small horses, dogs, cats: bred for different breeds
5. Types of Controlled Breeding
2. Inbreeding
Process of crossing individuals with similar characteristics
so those characteristics appear in offspring
- purpose: to maintain or intensify desireable traits
- individuals closely related (same species)
- more risk of passing recessive genetic defects
ex: poodles: joint deformities
maine coon cats: heart murmurs
6. Types of Controlled Breeding
3. Hybridization
Process of crossing individuals of different
but related species
- produces hybrids
- hybrid vigor: offspring are hardier than parents
(grow faster, larger, and are healthier)
Ex: cattle - disease resistant
corn – yield 10 times more than old varieties
broccoflower liger zonkey leopon tangelo
7. Types of Controlled Breeding
1. Induced Mutations (1927)
Polyploidy: common in plants, deadly in animals
- plants treated with chemicals to prevents cell plates
- resulting cells have multiple sets of chromosomes
- results in larger fruit and vegetables
8. • Techniques were forerunners modern
genetic engineering
• Today geneticists engineer changes
directly into an organismsDNA
9. GENETIC ENGINEERING
(GENE SPLICING/GENE CLONING)
• Process of direct gene manipulation
• Goal: to introduce new characteristics into
organisms to increase its usefulness
• Basic steps of genetic engineering involve:
1. isolation of gene
2. manipulation of gene/cloning gene -PCR
3. reintroduction of DNA into model organisms
animation: steps in cloning a gene
10. Genetic Engineering Techniques
I. Making Recombinant DNA
1. Restriction enzymes cut DNA into
fragments that can be isolated and
separated
- very specific proteins, recognizes and
cuts DNA at specific sequence into pieces
Ex: EcoRI – cuts DNA whenever
C-T-T-A-A-G sequence occurs
2. Production of recombinant DNA
- DNA composed of fragments of DNA
segments from at least two different
organisms
- restriction enzymes cut bacterial
plasmids (extra circular DNA molecules
in bacteria)
- plasmids have “sticky ends”
(unpaired bases)
- original DNA is attached to plasmid
sticky ends
11. Genetic Engineering Techniques
3. reintroduction of DNA into bacterial
vector
- recombinant DNA taken up with bacterial
DNA and now produced by bacterial cell
- recombinant DNA is isolated and CLONED
- PCR (polymerase chain reaction) induced
- purpose: to make 1000s of recombinant
plasmids
PCR animation
• DNA sequencing
- Process of reading exact order of bases in
fragment of DNA
- makes it possible for scientists to make
sure gene of interest has been cloned
rDNA: animation
12. Genetic Engineering Techniques
II. Microinjection
- Process of injecting genetic
material containing the new
gene into the recipient cell
- direct gene transfer, no
use of vectors
- in large cells done with
fine tipped glass needle
- somehow injected genes
find the host cell genes
and incorporate
themselves among them
Ex: most common
method of making
genetically altered
mice
13. Genetic Engineering Techniques
I. Bioballistics I. Electro and Chemical
Poration
- projectile methods that use
metal slivers to deliver the - process that creates pores
genetic material to the or holes in the cell
interior of the cell. membrane to allow direct
entry of new genes
- small slivers coated with
genetic material - done by bathing cells in
solutions of special
chemicals or weak electric
- once in the cell, genetic
current
material is transported to
nucleus where it is
incorporated among the host
genes
14. TRANSGENIC ORGANISMS /
GENETICALLY MODIFIED ORGANISMS
(GMO’s)
• organisms that contain foreign genes
Transgenesis
The use of recombinant DNA techniques to
introduce new characters (ie. genes) into
organisms (including humans) that were not
present previously.
15. Types GMO’s
I. Bacteria
-human DNA inserted in
bacterial plasmid
-recombinant produces large
volumes of proteins
Ex: human growth hormone
(HGH), insulin
16. Types GMO’s
II. Plants
- 1986: Howell
- inserted gene to producer enzyme
luciferase (fireflies)into tobacco plant
- enzyme in fireflies
- only produces enzyme in
conditions without light
(gene expression)
- cloned cells reproduced tobacco plant that
glowed in the dark
17. Making Transgenic Crops
Steps
2. extracting DNA
3. cloning a gene of
interest
4. designing the gene
for plant infiltration
5. transformation
6. plant breeding
18. Other Transgenic Plants
BT corn
(bacillus thuringiensis)
Soil bacterium that resists
insecticidal toxins: makes
corn resistant to pests and
less need for pesticides
19. Other Transgenic Plants
Calgene tomato
“Flavr Savr”
stays fresh longer
because enzyme to break
down pectin are reduced
by genetic alteration
24. Other examples of transgenic animals:
Transgenic chickens:
- grow faster and larger in close quarters
- produce more protein in their egg whites
- produce human protein drugs in their eggs
Transgenic pigs:
- produced by fertilizing normal eggs with
sperm cells that have incorporated foreign
DNA
- may someday be able to produce transgenic pigs
that can serve as a source of transplanted organs
for humans
video
25. Cloning Animals
1997 Wilmut (Scottish)
- cloned sheep “Dolly”
- process: nucleus of egg is replaced
with nucleus of adult , resultant
organism identical to adult
- now companies are making cloning
available to pet owners for their
beloved pets who die
- is this ethical?
Genetic Savings and Clone
26. Ethics of GMOs and Cloning
• Imagine cloning humans to make armies.
• Could clones and GMOs be patented?
• Are genetically modified livestock and agriculture
harmful?
• Would only perfect genetically engineered infants be
desirable.
27. APPLICATIONS OF G.E.
The first genetic fingerprint 1. DNA Fingerprinting
1984 (used in forensics)
Process of identifying and
distinguishing DNA of individuals
- each person has unique repeat
sequences and numbers of
non coding introns
- sample is taken and DNA is
extracted
- fragments of repeats of introns
are labeled and put into a
gel electrophoresis where they
separate
- create banding patterns which
Electrophoresis Animation Detail are unique for every human
28. APPLICATIONS OF G.E.
- Once banding patterns are apparent they are transferred to a
Southern Blot for identification
Southern blot animation
33. APPLICATIONS OF G.E.
• Gene therapy
Creating transgenic
humans to erase
genetic diseases
- recombinant DNA
put directly into human
cells or through virus
vectors
34. APPLICATIONS OF G.E.
1. Pollution control
- genetically altered
bacteria used to
decompose garbage
sewage, and petroleum
products
Unlike the left tower, which uses chemicals, the tower on the
right at this wastewater-treatment plant now uses bacteria-
covered foam blocks (inset) to eliminate the hydrogen sulfide
bubbling from treated sewage.
Deshusses/PNAS
35. APPLICATIONS OF G.E.
1. Medicines and Vaccines produced by
bacteria and viruses
- E coli: used to make human insulin
- hamster cell cultures: used to
make TPA (tissue plasminogen
activator)- dissolves blood clots in
heart attacks
- EPO (erythropoiten): increases
red blood cell production
- interferon: fights viral infections,
increases immunity
- vaccines
vaccine animation
36. APPLICATIONS OF G.E.
5. Agriculture and livestock
- hardier, disease and environmentally
resistant fruits and vegetables
- larger sturdier animals
37. HUMAN GENOME PROJECT
• begun in 1990: coordinated by US Dept of Energy and NIH
• purpose: - to identify the 20-25,000 genes in human DNA
- to determine sequences of 3 billion DNA base pairs
- to license info to biotech companies to foster new medical
applications
• international: US, England, China, France, Germany, Japan
• used combined genomes of anonymous small number of people
