Transcription, Translation
Review
Mutations
and
Genetic Modifications
Engage: One Wrong Letter
Explore:
What about Mistakes??
Mutation
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Any genetic material changes to a
cell
Modified Designer Babies
Types of Mutations

Point Mutations
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Base Pair Substitutions
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Base Pair Insertions and deletions
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Silent
Missense – new protein (Amino Acid Substitutions)
Nonsense – stop codon
Triplet Repeats
Frameshift Mutations
Variation in Chromosome Number
Chromosome Abnormalities
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Deletions
Translocations
Duplications
Inversions
Mutations: genetic material changes in a cell

Point mutations….
Changes in 1 or a few base
pairs in a single gene
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Base-pair substitutions:
•silent mutations
no effect on protein
•missense
∆ to a different amino acid
(different protein)
•nonsense
∆ to a stop codon and a
nonfunctional protein
Base-pair insertions or
deletions:
additions or losses of
nucleotide pairs in a gene;
alters the ‘reading frame’ of
triplets~frameshift mutation
Mutagens: physical and
chemical agents that change
DNA
Point Mutations
Base-Pair Substitution
Ex) Missense Mutation
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One Amino Acid Substituted for
Another
Sickle Cell Anemia

Valine is replaced with Glutamic
Acid
Sickle Cell Anemia
Base Pair Insertions
Triplet Repeats
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Occurs when
DNA is not
copied correctly
and a segment
is repeated
Ex) Huntington
Disease—CAG
Repeat
Deletion
Shifts Reading Frame

A deletion of
one or more
bases on a
section of the
chromosome.
Variation in Chromosome Number
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Having any
number of
chromosomes
that does not
equal 23 pairs.
Ex) Down
Syndrome –
3 Chromosome
21’s
Chromosome Abnormalities
Translocations

When one piece of
a chromosome
breaks off and
attaches to
another
chromosome
Duplications

Occurs during crossing over and
one chromosome ends up with
more genes than it received.
Inversions
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A reversal in the order of a
segment of a chromosome
Heredity, Mutations, and
Inheritable Diseases
Elaboration
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The next several slides will
show different types of
mutations.
Name each of the following
mutations.
What Type of Mutation?
Elaboration 2
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The next several slides will give
you information concerning a
particular mutation. On your
paper describe the overall affect
this mutation may cause..
Elaboration 2

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You will watch the movie
Lorenzo’s Oil and complete the
film guide questions.
This film will review several
concepts we have already
covered and will introduce
several new concepts to be
learned.
Genetic Modification
Where can it lead?