Mutations Mutations and and

Genetic ModificationsGenetic ModificationsTEKS BIO 6CTEKS BIO 6C

Instructions---READ Instructions---READ EVERYTHINGEVERYTHING

Today, you will learn about Today, you will learn about MUTATIONS. Follow the MUTATIONS. Follow the powerpoint, watching any videos powerpoint, watching any videos that may be presented, and fill in that may be presented, and fill in your notes as you go. Be sure your notes as you go. Be sure to read each slide to ensure you to read each slide to ensure you are completing your notes are completing your notes correctly.correctly.

Engage: One Wrong Letter-Engage: One Wrong Letter-You have seen this video before. You may choose to You have seen this video before. You may choose to watch it again, or move on to the next slide.watch it again, or move on to the next slide.

Explore:Explore:What about Mistakes??What about Mistakes??

MutationMutation Any changes to the genetic Any changes to the genetic

material (DNA) of a cellmaterial (DNA) of a cell

MutationsMutations

click the link above to watch the click the link above to watch the video before moving onvideo before moving on

How can mutations occur?How can mutations occur? Simple replication errors in DNASimple replication errors in DNA Environmental MutagensEnvironmental Mutagens

How Mutations Happen

Types of MutationsTypes of Mutations

Point Mutations Point Mutations Base Pair SubstitutionsBase Pair Substitutions

SilentSilent Missense – new protein (Amino Acid Substitutions)Missense – new protein (Amino Acid Substitutions)

Base Pair Insertions and deletionsBase Pair Insertions and deletions Triplet RepeatsTriplet Repeats Frameshift MutationsFrameshift Mutations

Variation in Chromosome NumberVariation in Chromosome Number Chromosome AbnormalitiesChromosome Abnormalities

DeletionsDeletions TranslocationsTranslocations DuplicationsDuplications InversionsInversions

Point Mutations- one base Point Mutations- one base change in the DNA sequencechange in the DNA sequence

Potential Results of Point MutationPotential Results of Point Mutation Observe what happens when the following Observe what happens when the following

Point Mutations Occur for each set:Point Mutations Occur for each set: CCA=LysCCA=Lys CCC=LysCCC=Lys GGA=ArgGGA=Arg GGU=ArgGGU=Arg UCU=StopUCU=Stop UCA=StopUCA=Stop

Amino acid meaning is not altered for each Amino acid meaning is not altered for each setset

This demonstrates a This demonstrates a Silent mutationSilent mutation

Potential Result of Point MutationPotential Result of Point Mutation

If the amino acid meaning is If the amino acid meaning is changed, cells could be alteredchanged, cells could be altered

Example: Example: Sickle Cell AnemiaSickle Cell Anemia Valine is replaced with Glutamic AcidValine is replaced with Glutamic Acid

Point Mutations:Point Mutations:Frame ShiftFrame Shift

Insertion or deletion of one or more bases into the Insertion or deletion of one or more bases into the sequence of the genesequence of the gene

How many DNA nucleotides can a ribosome read at How many DNA nucleotides can a ribosome read at one time?one time? three letters (called CODONS) code into 1 amino acid (“word”)three letters (called CODONS) code into 1 amino acid (“word”) adding or removing one letter changes each subsequent “word” adding or removing one letter changes each subsequent “word”

These mutations can make the DNA meaninglessThese mutations can make the DNA meaningless shortened and functionless protein shortened and functionless protein

ACTIVITYACTIVITY READ ALL DIRECTIONS ON THE READ ALL DIRECTIONS ON THE

NEXT SLIDE AFTER NEXT SLIDE AFTER PICKING UP PICKING UP THE PAGE FROM THE FRONTTHE PAGE FROM THE FRONT

READ ALL DIRECTIONS ON THE READ ALL DIRECTIONS ON THE NEXT SLIDE NEXT SLIDE BEFORE BEFORE COMPLETING ACTIVITYCOMPLETING ACTIVITY

READ ALL DIRECTIONS ON THE READ ALL DIRECTIONS ON THE NEXT SLIDE NEXT SLIDE BEFORE COMPLETING BEFORE COMPLETING ACTIVITYACTIVITY

ACTIVITY:ACTIVITY:“Modeling Chromosomal Mutations“Modeling Chromosomal Mutations””READ EVERYTHING READ EVERYTHING before moving onbefore moving on

First, read the directions on the “Modeling First, read the directions on the “Modeling Chromosomal mutations” page and follow the Chromosomal mutations” page and follow the directions about how to complete the “original directions about how to complete the “original chromosome.” chromosome.” Cut out the original chromosome Cut out the original chromosome and paste it to the top of your notes.and paste it to the top of your notes.

Continue with the slideshow AFTER completing Continue with the slideshow AFTER completing the directions on each slidethe directions on each slide

Cut out the colored diagram AND question and Cut out the colored diagram AND question and glue BOTH near the corresponding slide. glue BOTH near the corresponding slide. (either (either on the slide or below it)on the slide or below it)

DeletionDeletionFrame ShiftsFrame Shifts

A deletion of A deletion of one or more one or more bases on a bases on a section of the section of the chromosome.chromosome.

Color the “deletion” section Color the “deletion” section on your “modeling on your “modeling chromosomal mutations” chromosomal mutations” page, answer the question page, answer the question that follows, then cut and that follows, then cut and glue glue bothboth onto your slide. onto your slide.

Base Pair Insertions Base Pair Insertions (Triplet Repeats)(Triplet Repeats)

Occurs when Occurs when DNA is not DNA is not copied correctly copied correctly and a segment and a segment is repeatedis repeated

Ex) Huntington Ex) Huntington Disease—CAG Disease—CAG RepeatRepeat

Variation in Chromosome NumberVariation in Chromosome Number

Having any Having any number of number of chromosomes chromosomes that does not that does not equal 23 pairs.equal 23 pairs.

Ex) Down Ex) Down Syndrome – Syndrome – 3 Chromosome 3 Chromosome 21’s21’s

Chromosome AbnormalitiesChromosome Abnormalities

-Translocations-Translocations-Duplications-Duplications-Inversions-Inversions

TranslocationsTranslocations

When one piece of a When one piece of a chromosome breaks chromosome breaks off and attaches to off and attaches to another another chromosomechromosome

Color the “translocation” section on Color the “translocation” section on your “modeling chromosomal your “modeling chromosomal mutations” page, answer the mutations” page, answer the question that follows, then cut and question that follows, then cut and glue glue bothboth onto your slide. onto your slide.

DuplicationsDuplications

Occurs during Occurs during crossing over and one crossing over and one chromosome ends up chromosome ends up with more genes than with more genes than it received.it received.

Color the “duplication” section on your Color the “duplication” section on your “modeling chromosomal mutations” “modeling chromosomal mutations” page, answer the question that follows, page, answer the question that follows, then cut and glue then cut and glue bothboth onto your slide. onto your slide.

InversionsInversions A reversal in the order A reversal in the order

of a segment of a of a segment of a chromosomechromosome

Color the “inversion” section on your Color the “inversion” section on your “modeling chromosomal mutations” page, “modeling chromosomal mutations” page, answer the question that follows, then cut answer the question that follows, then cut

and glue and glue bothboth onto your slide onto your slide..

Elaboration 1Elaboration 1 The next several slides will give The next several slides will give

you information concerning a you information concerning a particular mutation.particular mutation.

Use the small blue papers to write Use the small blue papers to write your responses. LABEL EACH your responses. LABEL EACH SECTION CLEARLY!SECTION CLEARLY!

You will be graded on your You will be graded on your responses.responses.

DNA Sentence DNA Sentence - THE FAT CAT ATE THE WEE RAT - THE FAT CAT ATE THE WEE RAT Mutation -Mutation - THE FAT HAT ATE THE WEE RAT THE FAT HAT ATE THE WEE RAT

a)a) If this was a DNA sequence, what would this type of If this was a DNA sequence, what would this type of mutation be called?mutation be called?

b)b) Could this change cause the protein sequence to Could this change cause the protein sequence to change? How?change? How?

c)c) If this type of mutation occurred, what, if any, might be If this type of mutation occurred, what, if any, might be the possible consequence for the organism?the possible consequence for the organism?

Types of Mutations--1Types of Mutations--1

Original Sample Gene Original Sample Gene - THE FAT CAT ATE THE WEE RAT - THE FAT CAT ATE THE WEE RAT Mutation -Mutation - THE FAT KAT ATE THE WEE THE FAT KAT ATE THE WEE

RATRAT

a)a) If this was a DNA sequence, what would this type of If this was a DNA sequence, what would this type of point mutation be called?point mutation be called?

b)b) Was the meaning of the gene sentence altered? Was the meaning of the gene sentence altered?

c)c) If this type of mutation occurred, would there be any If this type of mutation occurred, would there be any consequence for the organism? Yes/No. Why or why consequence for the organism? Yes/No. Why or why not?not?

Types of Mutations--2Types of Mutations--2

Original Sample Gene Original Sample Gene - THE FAT CAT ATE THE WEE RAT - THE FAT CAT ATE THE WEE RAT Mutation -Mutation - THE FAT CAA TET HEW EER THE FAT CAA TET HEW EER

ATAT

a)a) If this was a DNA sequence, what would this type of If this was a DNA sequence, what would this type of mutation (chromosome abnormality) be called?mutation (chromosome abnormality) be called?

b)b) Could this change cause the polypeptide sequence to Could this change cause the polypeptide sequence to change? Yes/No change? Yes/No How?How?

Types of Mutations--3Types of Mutations--3

Original Sample Gene Original Sample Gene - THE FAT CAT ATE THE WEE RAT - THE FAT CAT ATE THE WEE RAT Mutation -Mutation - THE FAT ATE THE WEE RAT THE FAT ATE THE WEE RAT

a)a) If this was a DNA sequence, what would this type of If this was a DNA sequence, what would this type of mutation be called?mutation be called?

b)b) Could this change cause the polypeptide sequence to Could this change cause the polypeptide sequence to change? How?change? How?

Types of Mutations--4Types of Mutations--4

Types of Mutations--5Types of Mutations--5

Original Sample Gene Original Sample Gene - THE FAT CAT ATE THE WEE RAT - THE FAT CAT ATE THE WEE RAT Mutation -Mutation - THE FAT CAT XLW ATE THE WEE THE FAT CAT XLW ATE THE WEE

RATRAT

a)a) If this was a DNA sequence, what would this type of If this was a DNA sequence, what would this type of mutation be called?mutation be called?

b)b) Could this change cause the polypeptide sequence to Could this change cause the polypeptide sequence to change? How?change? How?

EvaluationEvaluation

The next several slides will The next several slides will show different types of show different types of mutations you’ve learned.mutations you’ve learned.

On the back of your sheet, write On the back of your sheet, write the type of mutation you think is the type of mutation you think is represented in the picture.represented in the picture.

What Type of Mutation?--6What Type of Mutation?--6

What Type of Mutation?--7What Type of Mutation?--7

What Type of Mutation?--8What Type of Mutation?--8

What Type of Mutation?--9What Type of Mutation?--9

What Type of Mutation?--10What Type of Mutation?--10

Genetic Modification--Where Genetic Modification--Where can it lead?can it lead?