Download DNA Technology

DNA Technology
Chapter 13
Lab Biology
Genetically Modified Organisms
• Modified genome of an organism
▫ Takes DNA from multiple sources and combine
them to form a new genome
 DNA from same species
 DNA from different species- Transgenic organisms
Crops that
• Do NOT need fertilizer
• Disease resistant plants
• Insect resistance
• Herbicide resistant
• Salt-tolerant plants
See the hornworm beginning to form
at the leaves!
This hornworm eats and destroys the
tomato plant!
Hornworms attack tomato and tobacco
plants
Golden Rice
• Insertion of genes
(Recombinant
DNA) -produce a
precursor of
vitamin A
• Helps areas where
there is a shortage
of dietary vitamin A
White
rice
Golden
rice
Dangers of GMO’s
• Unexpected
allergies
• Introduction of
new genes to a
population
▫ SUPER
WEEDS
• Creation of
invasive
species
DNA Fingerprints
• I. DNA Fingerprints  pattern of bands
made up of specific fragments from an
individual’s DNA
• USED FOR:
▫ DETECTION OF A RELATIVE
▫ SIMILARITIES BETWEEN
SPECIES
▫ FORENSICS
Forensics- DNA fingerprinting
• VNTR- Variable number
tandem repeats
• Show variations in length
between individuals
• Can be compared with
DNA databases (CODIS)
How do you make DNA fingerprints?
• RFLP (restriction fragment length
polymorphism) analysis
▫ 1. extract DNA from specimen using restriction
enzymes
▫ 2. separate fragments of DNA using
electrophoresis (separates DNA according to
size and charge)
▫ 3. placed in wells made on gel and run electric
current through gel
▫ 4. blotted onto filter paper/ photgraphic
film.
• Electrophoresis “electro” = electricity “phoros” = to
carry across
• Determine the genetic differences and the
evolutionary relationship among species of
organisms
• Method that separates on basis of size, electric charge
and other physical properties
Can you tell who could be the
father? Circle matching DNA bands
Are you related? Linkage analysis
• A mother, father, and their four “children”
Accuracy of DNA Fingerprints
• DNA fingerprints are very accurate
• However, genetic tests can only
absolutely disprove, not prove,
relationship!
• Courts accept 99.5% accuracy as
proof of alleged paternity
Polymerase Chain Reaction (PCR)
• Used when you only have a TINY piece
of DNA
• Quickly make many copies of selected
segments of the available DNA
• Use a PRIMER to initiate replication
• DNA doubles every 5 minutes
PCR is used for:
• 1. Forensics
▫ increased the amount of DNA
evidence for testing
• 2. Diagnosing genetic disorders
• 3. Studying ancient fragments of
DNA (tiny amounts)
Vaccines
• Used to improve immunity
against certain diseases
• Present- Uses weakened or
dead versions of the
microorganism
▫ Risk of the body not being
able to handle the infection
▫ Risk of dead organisms
reviving
DNA Vaccines
• Future- DNA vaccines- using specific parts of
DNA that code for antigens
▫ No risk of infection
Avian fluvirus
Cloning
•
•
Growing a population of genetically
identical cells from a single cell.
1997 - Ian Wilmut with Dolly, the cloned
sheep
Uses
• Cloning can be used to test for
genetic diseases
• Regenerate nerves or spinal cord
tissue
• Help in plastic surgery
• Clone organs for transplantation
• Grow skin grafts for burn victims
• Manufacture bone, fat, and cartilage
Ethical Issues
What are the implications of cloning?
How will cloning affect the medical field?
What will be the effect on the gene pool?
Is there potential for abuse?
How should it be regulated?
Would you consider cloning yourself?
Stem Cells
• Self renewing-regenerate
• Multi-potency- can become many different types
of cells
• Uses
▫
▫
▫
▫
▫
Basic Knowledge of Human Development
Models of Human Disease
Transplantation-Cell Replacement
Drug Development
Organogenesis