DNA TECHNOLOGY

1
DNA TECHNOLOGY
2
DNA TECHNOLOGY

• How can we use DNA?
• Solve crimes, diagnose genetic disorders, solve
  paternity cases, compare species, study and cure
  disease, modify foods, etc.
• Where do we get DNA samples?
• Blood, skin, hair, semen, etc.
• Human DNA
• 99.9 the same 0.1 different

3
Human Genome Project

• Completed in 2003
• Map and sequence human genome
• Find where all genes are located and sequence DNA
  
• Uses diagnose genetic disorders
• Gene therapy
• Insert normal genes into cells to correct genetic
  disorders

4
DNA Extraction

• Open cells to isolate DNA from other cell parts

5
Polymerase Chain Reaction (PCR)

• Used to amplify regions of DNA (make many copies
  of a small amount of DNA)
• Heat DNA to denature/unwind
• Add primers (short segments of DNA) that match
  the gene you want to copy
• Add polymerase and nucleotides
• Repeat!

6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
Restriction Enzymes

• cutting DNA
• Large DNA molecules are cut into smaller
  fragments
• Restriction enzymes recognize and cut DNA at
  specific sequences

14
Restriction Enzymes

• Come from bacteria
• Ex Eco RI
• EEscherichia(genus)
• cocoli(species)
• RRY13(strain)
• IFirst identified - Order ID'd in bacterium
• Cut DNA at specific point

15
Each Restriction Enzyme cuts DNA at a specific
base sequence. For example, EcoRI always cuts DNA
at GAATTC as indicated below. The sequence
GAATTC appears three times in the DNA strand
below. As a result, the strand is cut into four
pieces.                                         
                                          
16
Restriction Enzymes

• Blunt Ends
• When RE cuts straight across DNA

• Sticky Ends
• Will join with other ends

AG CT TC GA
GG CC CC GG
G GATCC CCTAGG G
A AGCTT TTCGA
A
G AATTC CTTAA
G
17
Gel Electrophoresis

• A way to separate DNA, RNA, or proteins based on
  size
• Put sample in a gel and add electricity
• DNA fragments move
• DNA has negative charge (moves to end)
• Smaller fragments travel farthest
• Bands are stained and compared to a standard to
  estimate size

18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
Using Gel Electrophoresis

• Solving a Crime
• Compare the DNA bands
• Must be an exact match
• Paternity Test
• Compare DNA bands
• Childs DNA must come from mother or father

23
(No Transcript)
24
(No Transcript)
25
DNA Fingerprinting

• DNA sample is copied by PCR
• DNA is cut into fragments by using restriction
  enzymes
• Fragments of DNA are separated by gel
  electrophoresis
• DNA is then compared for a match

26
Genetic Engineering

• Genetic Engineering Recombinant DNA Technology
  Genetic Recombination
• Cutting (cleaving) DNA from one organism into
  small fragments and inserting the fragments into
  a host organism of the same or different species
• The host then uses the foreign DNA as its own

27
Genetic Engineering

• Recombinant DNA DNA fragments that have been
  connected (recombined) from different species
• Transgenic Organsims organisms that contain
  functional recombinant DNA (foreign DNA)

28
Genetic Engineering

• How to Do It?
• Isolate foreign DNA fragment
• Attach DNA fragment to a vehicle
• Transfer the vehicle into the host organism

29
Isolate Foreign DNA

• Cut DNA from chromosome
• Restriction Enzymes bacterial proteins that
  have the ability to cut both strands of DNA at a
  certain sequence
• Cut at palindromes
• Blunt ends (cut straight across)
• Sticky ends (leave single-stranded ends that can
  join with other ends)

30
Each Restriction Enzyme cuts DNA at a specific
base sequence. For example, EcoRI always cuts DNA
at GAATTC as indicated below. The sequence
GAATTC appears three times in the DNA strand
below. As a result, the strand is cut into four
pieces.                                         
                                          
31
Fragment Attached to Vehicle

• Vector used to carry DNA from one species to a
  host (can be biological or mechanical)
• Plasmid small ring of bacterial DNA
• Micropipette
• Gene Gun
• Gene Splicing rejoining DNA fragments
• Cut DNA and plamsid with same restriction enzyme
  ends match and join

32
Fragment Attached to Vehicle

• If a plasmid and the foreign DNA are cut with the
  same restriction enzyme, the ends will attach and
  join
• The recombinant DNA in the plasmid (vector) is
  put into a bacterial cell to clone the DNA

33
Uses of Recombinant Bacteria

• Industry
• To beak down pollutants
• Clean up oil spills
• Medicine
• Make insulin, etc.
• Transgenic organisms to study disease
• Agriculture
• Remove bacterial gene that causes frost in
  strawberries
• Transgenic plants to resist herbicides or
  increase protein production