Transcription, TranslationTranscription, TranslationReviewReview

Mutations Mutations and and

Genetic ModificationsGenetic Modifications

Engage: One Wrong LetterEngage: One Wrong Letter

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

MutationMutation Any genetic material changes to a Any genetic material changes to a

cellcell Modified Designer BabiesModified Designer Babies

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) Nonsense – stop codonNonsense – stop codon

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

Mutations: Mutations: genetic material changes in a cellgenetic material changes in a cell

Point mutationsPoint mutations….….

Changes in 1 or a few base Changes in 1 or a few base pairs in a single genepairs in a single gene

Base-pair substitutionsBase-pair substitutions:: ••silent mutationssilent mutations

no effect on protein no effect on protein • •missense missense ∆ to a different ∆ to a different amino acid (different protein) amino acid (different protein) • •nonsensenonsense ∆ to a stop codon ∆ to a stop codon and and a nonfunctional a nonfunctional proteinprotein

Base-pair insertions or Base-pair insertions or deletions:deletions: additions or losses of additions or losses of nucleotide pairs in a gene; nucleotide pairs in a gene; alters the ‘reading frame’ of alters the ‘reading frame’ of triplets~triplets~frameshift mutationframeshift mutation

Mutagens:Mutagens: physical and physical and chemical agents that change chemical agents that change DNADNA

Point MutationsPoint Mutations

Base-Pair Substitution Base-Pair Substitution Ex) Missense MutationEx) Missense Mutation

One Amino Acid Substituted for One Amino Acid Substituted for AnotherAnother

Sickle Cell AnemiaSickle Cell Anemia Valine is replaced with Glutamic Valine is replaced with Glutamic

AcidAcid

Sickle Cell AnemiaSickle Cell Anemia

Base Pair Insertions Base Pair Insertions Triplet RepeatsTriplet 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

DeletionDeletionShifts Reading FrameShifts Reading Frame

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.

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 – 3 Syndrome – 3 Chromosome Chromosome 21’s21’s

Chromosome AbnormalitiesChromosome Abnormalities

TranslocationsTranslocations

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

DuplicationsDuplications

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

InversionsInversions A reversal in the order of a A reversal in the order of a

segment of a chromosomesegment of a chromosome

Heredity, Mutations, and Heredity, Mutations, and Inheritable DiseasesInheritable Diseases

ElaborationElaboration

The next several slides will The next several slides will show different types of show different types of mutations.mutations.

Name each of the following Name each of the following mutations.mutations.

What Type of Mutation?What Type of Mutation?

Elaboration 2Elaboration 2

The next several slides will give The next several slides will give you information concerning a you information concerning a particular mutation. On your particular mutation. On your paper describe the overall affect paper describe the overall affect this mutation may cause..this mutation may cause..

Elaboration 2Elaboration 2

You will watch the movie You will watch the movie Lorenzo’s Oil and complete the Lorenzo’s Oil and complete the film guide questions.film guide questions.

This film will review several This film will review several concepts we have already concepts we have already covered and will introduce covered and will introduce several new concepts to be several new concepts to be learned.learned.

Genetic ModificationGenetic ModificationWhere can it lead?Where can it lead?