the techniques involved in genetic engineering. in addition to the information in this presentation,...
TRANSCRIPT
Manipulating DNAThe Techniques Involved in Genetic
Engineering
Before we begin…In addition to the information in this
presentation, you should also be familiar with the corresponding information found on
pages 319-325 in your textbook
Genetic EngineeringGenetic engineering
Altering the genetic code of a living organism
in other words…
Changing the DNA of a living thing on purpose
The Changes…Selective Breeding
InbreedingHybridization
Molecular manipulationInducing mutationsDNA splicing
Selective BreedingInbreeding
The continued breeding of individuals with similar characteristics
While inbreeding does maintain
the characteristics of the breed, it also makes genetic defects more
common
Selective BreedingHybridization
The process of mating two organisms from different species to create a hybrid
Selective BreedingHybridization
In plants
Selective BreedingHybridization
In animals
Selective BreedingHybridization
In animals
Selective BreedingHybridization
In animals
Molecular ManipulationInducing mutation
Using artificial means (for example: radiation or drugs) to cause specific mutations in living organisms
Molecular ManipulationInducing mutation
Certain mutation causes extra chromosomes leading to bigger and stronger fruiting plants
Molecular ManipulationInducing mutation
Certain mutation causes oil-eating bacteria
Used to clean up oil spills!
Molecular ManipulationDNA splicing
Taking a segment of DNA from one organism and putting it into the DNA of another organism
Let’s go through the process…
Molecular ManipulationDNA splicing
Extracting the DNA Getting the DNA out of the cell and separating it
from the other cell parts
Molecular ManipulationDNA splicing
Cutting the DNA Whole DNA molecules are too large to be analyzed Scientists cut them into smaller pieces using
restriction enzymes
More on Restriction EnzymesA restriction enzyme is a specialized
enzyme that cuts the DNA molecule at a very specific sequence
There are hundreds of restriction enzymes, each one cutting the DNA at a specific sequence
Think of restriction enzymes like a lock and key: a restriction enzyme will cut a DNA sequence only it matches precisely
More on Restriction EnzymesEcoR I SmaI
Cuts the DNA at the sequence CTTAAG, between the A and G
Cuts the DNA at the sequence CCCGGG, between the C and G
A AAA
A GGGC
C CT TTT
TGC
A AAA
A GGGC
C CT TTT
TGC
A
A
AA
A G
G GC
C
C
T T
TT
T
GC
A GGGC
C CTGCAT
GC
GC G
CGC
A GGGC
C CTGCAT
GC
GC G
CGC
A GCT
GC
GC
GGC
CGCATG
CGC
Molecular ManipulationDNA splicing
Pasting the DNA Using and enzyme called DNA ligase to attach
segments of DNA
Molecular ManipulationReal world application:
Analyzing DNAGel Electrophoresis
DNA that has been cut with restriction enzymes is placed in wells at one end of a porous gel
An electric voltage is applied to the gel, and the DNA which has a (-) charge moves away from the (-) charge and toward the (+) charge
The smaller the DNA particle, the farther it is able to move through the porous gel
This allows scientists to compare the DNA sequences from different individuals, or determine the relative sizes or particular genes
Analyzing DNAGel Electrophoresis