Genetic Mutations. What Are Mutations? Changes in the nucleotide sequence of DNA Changes in the...
-
Upload
jesse-miller -
Category
Documents
-
view
222 -
download
2
Transcript of Genetic Mutations. What Are Mutations? Changes in the nucleotide sequence of DNA Changes in the...
Genetic MutationsGenetic Mutations
What Are Mutations?What Are Mutations?
Changes in the nucleotide sequence Changes in the nucleotide sequence of DNAof DNA
May occur in body cells and are not May occur in body cells and are not passed to offspringpassed to offspring
May occur in gametes (eggs & May occur in gametes (eggs & sperm) and be passed to offspringsperm) and be passed to offspring
Are Mutations Helpful or Are Mutations Helpful or Harmful?Harmful?
Mutations happen regularly and Mutations happen regularly and often neutral often neutral
Many mutations are naturally Many mutations are naturally repaired by enzymesrepaired by enzymes
Causes of mutations:Causes of mutations:NaturalNaturalChemicalsChemicalsRadiationRadiationOther environmental factorsOther environmental factors
Are Mutations Helpful or Are Mutations Helpful or Harmful?Harmful?
Some mutations are harmful and Some mutations are harmful and can cause:can cause:CancerCancerBirth defectsBirth defectsPhysical impairmentsPhysical impairmentsOther life altering conditionsOther life altering conditions
Some mutations may improve an Some mutations may improve an organism’s survival organism’s survival This is know as evolutionThis is know as evolution
Types of MutationsTypes of Mutations
Chromosome Mutations and Gene Chromosome Mutations and Gene MutationsMutations
Chromosome Chromosome MutationsMutations
May Involve:May Involve:Changing Changing
the the structurestructure of of a a chromosomechromosome
The The loss or loss or gaingain of part of of part of a a chromosomechromosome
Types of Chromosome Types of Chromosome MutationsMutations
Five types exist:Five types exist:DeletionDeletionInversionInversionTranslocationTranslocationNondisjunctionNondisjunctionDuplicationDuplication
DeletionDeletionDue to Due to
breakage, abreakage, a piecepiece of a chromosome is of a chromosome is
lost lost
InversionInversionChromosome segment Chromosome segment breaks offbreaks offSegment flips around Segment flips around backwardsbackwards
Segment Segment reattachesreattaches
DuplicatioDuplicationn
Occurs Occurs when a gene when a gene sequence is sequence is
repeatedrepeated
TranslocatiTranslocationon
Involves Involves two two chromosomes chromosomes
that not that not homologoushomologous
PartPart of one of one chromosome is chromosome is transferred to transferred to
anotheranother chromosomeschromosomes
NondisjunctionNondisjunction
Caused by a failure of chromosomes to Caused by a failure of chromosomes to separate during meiosisseparate during meiosisAs a result, the gamete will have too As a result, the gamete will have too
many or too few chromosomesmany or too few chromosomes
Gene MutationsGene Mutations
What are What are Gene Gene
Mutations?Mutations?Change in the Change in the
nucleotide sequence nucleotide sequence of of a genea gene
May only involve a May only involve a single nucleotidesingle nucleotide
May be due to May be due to copying copying errorserrors, , chemicalschemicals, ,
virusesviruses, etc., etc.
Types of Gene Types of Gene MutationsMutations
Include:Include:Point MutationsPoint MutationsSubstitutionsSubstitutionsInsertionsInsertionsDeletionsDeletionsFrameshiftFrameshift
Point MutationPoint Mutation
What is it?What is it?
Change of a Change of a singlesingle nucleotide nucleotide
Includes the Includes the deletion, insertion, deletion, insertion, or substitution of or substitution of ONEONE nucleotide in nucleotide in a genea gene
Example:Example:
Sickle Cell Sickle Cell disease disease is the is the result of one result of one nucleotide nucleotide substitutionsubstitution
Occurs in the Occurs in the hemoglobin hemoglobin genegene
Frameshift MutationFrameshift Mutation
Inserting or Inserting or deleting one or deleting one or more nucleotidesmore nucleotides
Changes the Changes the ““reading framereading frame”” like changing a like changing a sentencesentence
Causes proteins to Causes proteins to be built incorrectlybe built incorrectly
Food incFood incClass DiscussionClass Discussion
DiscussionDiscussion
See teacher for detailsSee teacher for details
Modern GeneticsModern Genetics
ObjectivesObjectives
Describe ways of producing organisms with Describe ways of producing organisms with desired traitsdesired traits
State the goal of the human genome projectState the goal of the human genome project
Selective Breeding Selective Breeding
Definition: The process of selecting organisms Definition: The process of selecting organisms with desired traits to be the parents of the with desired traits to be the parents of the next generationnext generation
This process has been used for hundreds of This process has been used for hundreds of yearsyears
Two Types:Two Types: Inbreeding- crossing two individuals that have Inbreeding- crossing two individuals that have
similar characteristicssimilar characteristics Hybridization- crossing two genetically different Hybridization- crossing two genetically different
individuals individuals
CloningCloning
Cloning- Cloning- a technique used to produce a technique used to produce offspring with desired traits (identical to the offspring with desired traits (identical to the traits of another organism) traits of another organism)
Clone- Clone- an organism that has identical gene an organism that has identical gene as the one from which it was producedas the one from which it was produced
WATCHWATCH - BrainPop: Dolly the Sheep - BrainPop: Dolly the Sheep
Genetic EngineeringGenetic Engineering
Genetic engineeringGenetic engineering- genes from one - genes from one organism are transferred into the DNA of organism are transferred into the DNA of anotheranother
Examples ….Examples ….
Gene therapy- Gene therapy- use of genetic engineering to use of genetic engineering to correct genetic disorders. correct genetic disorders.
Concerns…Concerns…
The Human Genome The Human Genome ProjectProject
Genome- Genome- all of the DNA in one cell of an organismall of the DNA in one cell of an organism
Goal of the Human Genome Project:Goal of the Human Genome Project: Identify the sequence of every gene in the human Identify the sequence of every gene in the human
genome genome
Interesting Facts:Interesting Facts: The DNA of humans consists of at least 30,000 genesThe DNA of humans consists of at least 30,000 genes Each gene has about 3,000 bases (A, T, G, C)Each gene has about 3,000 bases (A, T, G, C)
Other Uses:Other Uses: DNA FingerprintingDNA Fingerprinting
Technology used in the Human Genome Project can Technology used in the Human Genome Project can be used to identify people and show whether people be used to identify people and show whether people are relatedare related