MUTATIONSMUTATIONS

Changes in Changes in DNADNA that affect genetic that affect genetic informationinformation

MutationsMutations

A change in the order of the nucleotide bases in A change in the order of the nucleotide bases in DNA is a mutationDNA is a mutation

It can change the type of proteins a cell It can change the type of proteins a cell producesproduces

No freckles

Freckles

Gene MutationsGene Mutations

Point Mutations – changes Point Mutations – changes in one in one or a fewor a few nucleotides nucleotides SubstitutionSubstitution

THE FAT THE FAT CCAT ATE THE RATAT ATE THE RAT THE FAT THE FAT HHAT ATE THE RATAT ATE THE RAT

THE FAT CAT ATE THE RATTHE FAT CAT ATE THE RAT THE THE BBAT CAT ATE THE RATAT CAT ATE THE RAT

Gene MutationsGene Mutations Frameshift Mutations – shifts the Frameshift Mutations – shifts the LETTERSLETTERS of the of the

genetic message so that the genetic message so that the protein protein may not be may not be able to perform its able to perform its function.function. InsertionInsertion

THE FAT CAT ATE THE RATTHE FAT CAT ATE THE RAT THE FAT THE FAT HHCA TAT ETH ERA TCA TAT ETH ERA T

DeletionDeletion TTHHE FAT CAT ATE THE RATE FAT CAT ATE THE RAT TEF ATC ATA TET GER ATTEF ATC ATA TET GER AT

H

H

InsertionInsertion

DeletionDeletion

Chromosomal MutationsChromosomal Mutations

Changes in number and structure of Changes in number and structure of entire chromosomes entire chromosomes

Chromosome MutationsChromosome Mutations

Deletion- loss of part or all of Deletion- loss of part or all of chromosome.chromosome.

Duplication –extra copies or parts of Duplication –extra copies or parts of chromosome.chromosome.

Inversion-reverse direction of Inversion-reverse direction of chromosome.chromosome.

Translocation – occurs when chromosome Translocation – occurs when chromosome breaks and attaches to another breaks and attaches to another chromosome.chromosome.

Types of Chromosomal Types of Chromosomal Mutation: DeletionMutation: Deletion

OriginalOriginalABC * DEFABC * DEF

ABC *ABC *DEFDEF

Chromosome 5 Deletion:Chromosome 5 Deletion:Cri du Chat SyndromeCri du Chat Syndrome

Types of Chromosomal Types of Chromosomal Mutation: DuplicationMutation: Duplication

AABBBC * DEFBC * DEF

OriginalOriginalABC * DEFABC * DEF

Types of Chromosomal Types of Chromosomal Mutation: TranslocationMutation: Translocation

OriginalOriginalABC * DEFABC * DEFGHI*JKLGHI*JKL

ABC * ABC * JKLJKL

GHI * GHI * DEFDEF

Chromosome 21 Chromosome 21 Duplication & Duplication & Translocation:Translocation:Down SyndromeDown Syndrome

Types of Chromosomal Types of Chromosomal Mutation: InversionMutation: Inversion

AAEDED * * CBCBFFOriginalOriginalABC * DEFABC * DEF

Significance of MutationsSignificance of Mutations

• Most are neutralMost are neutral

• Eye colorEye color

• Birth marksBirth marks

• Some are harmfulSome are harmful

• Sickle Cell AnemiaSickle Cell Anemia

• Down SyndromeDown Syndrome

• Some are beneficialSome are beneficial

• Sickle Cell Anemia gives resistance to Sickle Cell Anemia gives resistance to MalariaMalaria

• Immunity to HIVImmunity to HIV

What Causes What Causes Mutations?Mutations? Mutations can be inherited. Mutations can be inherited.

Parent to childParent to child

Mutations can be acquired.Mutations can be acquired.Environmental damageEnvironmental damageMistakes when DNA is copied Mistakes when DNA is copied