Download 9.1 Manipulating DNA

9.1 Manipulating DNA
•Set up Cornell Notes on
pg. 15
•Topic: 9.1 Manipulating
DNA
•Essential Question:
1. Suppose you cut DNA.
You know that you
should find four DNA
fragments on a gel, but
only three appear, and
one fragment is very
large. Explain what
happened?
9.1Ions,
Manipulating DNA
2.1 Atoms,
and Molecules
1. Suppose you cut DNA. You know
that you should find four DNA
fragments on a gel, but only three
appear, and one fragment is very
large. Explain what happened?
KEY CONCEPT
Biotechnology relies on
cutting DNA at specific
places
9.1 Manipulating DNA
• P.14
9.1 Manipulating DNA
Points to Ponder (Top of p. 14)
A natural disaster strikes. Families are
separated. How can they be reunited?
If a body is found and the person cannot
be identified by looks, how can we identify
them?
What types of identifiers do we have?
9.1 Manipulating DNA
A natural disaster strikes. Families are separated. How
can they be reunited?
If a body is found and the person cannot be identified by
looks, how can we identify them?
What types of identifiers do we have?
• DNA- skin, sperm, saliva, blood
• Fingerprinting
• Teeth
9.1 Manipulating DNA
Unidentified body found after the sinking of the RMS Titanic known as
“The Unknown Child”
NO. 4 - MALE - ESTIMATED AGE, 2 - HAIR, FAIR.
CLOTHING - Grey coat with fur on collar and cuffs;
brown serge frock; petticoat; flannel garment; pink woolen
singlet; brown shoes and stockings.
No marks whatever.
Possibly third-class.[3]
9.1 Manipulating DNA
The sailors aboard the Mackay-Bennett, who were
very upset by the discovery of the unknown boy's
body, paid for a monument, and he was buried on 4
May 1912 with a copper pendant placed in his coffin
by recovery sailors that read "Our Babe."
9.1 Manipulating DNA
• His body, identified as that of a child around two years old, was
initially believed to be that of either a two-year-old Swedish boy,
Gösta Pålsson; a two-year-old Irish boy, Eugene Rice, or Eino
Viljami Panula, a 13-month old Finnish baby
• However, with improved DNA testing available in 2007, Canadian
researchers at Lakehead University in Thunder Bay tested the
child's HVS1, a type of mitochondrial DNA molecule, and it did not
match the Panula family.
9.1 Manipulating DNA
• Finally identified in 2007 using DNA
evidence
• DNA extracted from the exhumed
remains and DNA provided by a
surviving maternal relative helped
positively match the remains to Sidney
Leslie Goodwin (1910-1912), and the
reidentification was announced on 30
July 2007
• The Goodwins and their 6 children
were third class passengers and all
perished
9.1 Manipulating DNA
KEY CONCEPT
Biotechnology relies on cutting DNA at specific
places.
Baby 81 was
rescued after the
2004 Indian Ocean
tsunami. He was
reunited with his
parents by using
DNA
fingerprinting
technology
9.1 Manipulating DNA
Biotechnology allows us to
•
•
•
•
Produce transgenic organisms
Clone
Study diseases and evolution
Produce medical treatments for people with illnesses
9.1 Manipulating DNA
• DNA cannot be picked up and rearranged by hand
• Therefore, scientists must be able to work with DNA
without being able to see it, or handle it directly
9.1 Manipulating DNA
Scientists use several techniques to manipulate DNA.
• Chemicals, computers, and bacteria are used to work
with DNA.
• Scientists use these tools in genetics research and
biotechnology.
9.1 Manipulating DNA
• Restriction enzymes act as “scissors” by cutting DNA
– allow scientists to more easily study and manipulate
genes
– cut DNA at a specific nucleotide sequence called a
restriction site
DNA
Restriction
enzyme
9.1 Manipulating DNA
• Different restriction enzymes cut DNA in different
ways.
– each enzyme has a different restriction site
9.1 Manipulating DNA
– some cut straight across and leave “blunt ends”
– some make staggered cuts and leave “sticky ends”
Sticky
ends
9.1 Manipulating DNA
Between what nucleotides does this restriction enzyme cut
between?
T and C or
C and T
9.1 Manipulating DNA
Restriction Enzymes (Middle of p. 14)
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
1. How many fragments are produced?
2. Are all the fragments the same length?
3. Please organize the fragments from biggest to
smallest.
4. How many nucleotides in each segment when
organized?
9.1 Manipulating DNA
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
How many fragments are produced? 3
Are all the fragments the same length? No
Please organize the fragments from biggest to
smallest. ACGACCT/AGGACG/ATT
How many nucleotides in each segment when
organized? 7, 6, 3
9.1 Manipulating DNA
• Restriction Enzyme Video
2m39s
9.1 Manipulating DNA
•
After DNA has been cut, several different things can be
done with it:
– The gene can be studied
– The gene can be placed in another organism
• But first, the DNA fragments have to be separated
from one another
• Sorted according to their size
9.1 Manipulating DNA
• Gel electrophoresis is used to separate DNA fragments by
size.
– A DNA sample is cut with restriction enzymes
– Electrical current pulls DNA fragments through a gel
9.1 Manipulating DNA
– Smaller fragments move faster and travel farther
than larger fragments
– Fragments of different
sizes appear as bands
on the gel
9.1 Manipulating DNA
• A restriction map shows the lengths of DNA fragments
between restriction sites.
– only indicate size, not
DNA sequence
– useful in genetic
engineering
– used to study
mutations
9.1 Manipulating DNA
Restriction Enzymes (Middle of p. 14)
Restriction enzyme: cuts between T and A
ATTACGACCTAGGACG
You organized the fragments from biggest to smallest.
ACGACCT (7)
AGGACG (6)
ATT (3)
9.1 Manipulating DNA
-
Grab 3 colors. Please organize the fragments from
biggest to smallest on this restriction map.
ACGACCT (7)
AGGACG (6)
ATT (3)
Draw and
complete this
restriction map
on the bottom
of pg. 14
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10
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1
0
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9.1 Manipulating DNA
“Who Ate the Cheese?” Warm-Up
• Please complete the warm-up by yourself
• Books open to 266-267
• 5 mins
9.3 DNA Fingerprinting
Who Ate the Cheese?
Practice Gel Electrophoresis-Restriction Enzyme Lab
Objective: You will examine crime evidence and model the process of gel electrophoresis and
DNA fingerprinting to identify the person who ate the Queen’s cheese.
• Read the Royal Incident Report
• You are looking for the sequence
CCGG
GG CC
– The restriction enzyme always cuts between the
C /G
– All cuts will leave blunt ends
• Count the number of base pairs in each fragment of
DNA
– Record the # on the bottom of each DNA
fragment
• Make a restriction map to identify who, if anyone,
is guilty of eating the queen’s cheese