Albinism is also known as Oculocutaneous albinism, Ocular albinism and, Hermansky-Pudlak syndrome.
Genetic Alterations. Albinism Albinism Robin Peacock.
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Transcript of Genetic Alterations. Albinism Albinism Robin Peacock.
Genetic AlterationsGenetic Alterations
AlbinismAlbinism
AlbinismAlbinism
Robin
Peacock
Squirrel
Coyote
AlbinismAlbinism
AlbinismAlbinism
Elephant
African Mangaby
Albinism - SnowflakeAlbinism - SnowflakeOnly albino gorilla know to science
and died of skin cancer.
Far SightedFar Sighted
HypertrichosisHypertrichosis
A hair growing disorder.
Lack of ClavicleLack of Clavicle
Lobster Claw FootLobster Claw Foot
Thalidamide BabyThalidamide Baby
Caused from a Birth Control Pill in England.
Tri D BabyTri D Baby
Turner SyndromeTurner Syndrome
When females have only a single x chromosome instead of two.
It is non lethal.
Human TailHuman Tail
Genetic Genetic EngineeringEngineering
Genetic EngineeringGenetic Engineering
The ability to move genetic material (genes) from one organism to another
Genetic EngineeringGenetic Engineering
History1000’s years people have changed
the characteristics of plants and animalsselective breedingexploitation of mutations
dreamed of being able to artificially create mutations
What is Genetic Engineering?What is Genetic Engineering?
Involves the manipulation of genes (DNA sequence) within a cell or organism to produce a desired result.
a change in the genetic makeup of an organism through: deliberate addition (insertion) Removal (deletion) intentional mutation of DNA
Most commonly it involves the transfer of a gene from one organism to another.
ExamplesExamples
Bacteria produce Human insulin needed for diabetics
Transgenic pigs produce human Factor VIII, a blood-clotting agent needed by hemophiliacs
Bacteria produce hormone BST which helps control the production of milk.
Steps in Genetic Engineering
1) Isolate the gene and cut it using restriction enzymes
2) Cut bacterial DNA using restriction enzymes
3) Splice the gene into bacterial DNA by attaching “sticky” ends
Steps in Genetic Engineering
4) Place the engineered bacterial DNA into a bacteria cell
5) Clone the bacteria and collect the product
What Genetic Engineering
Can Do
Agriculture
1. Plants resistant to virus, salt, drought 2. Plants resistant to frost and heat 3. Plants resistant to insects 4. Plants resistant to roundup 5. Animals that produce desired chemicals
in their products (TPA in milk) 6. Enhanced meat and milk production
Medicine
1. Production of pharmaceuticals (insulin, TPA, interferon)
2. Study of human cancer in mice3. Map the human genome4. Correct genetically caused
diseases
Clean up the environment
1. Bacteria to feed on oil slicks and toxic chemicals
2. Convert waste materials into useful products (cellulose into plastic)
3. Improve efficiency of industrial processes
Using Bacteria as Factories
1. Human Insulin2. Human Growth Hormone3. BST4. TPA -- clot dissolving formula5. Vaccines
Bovine somatotropin BST
A hormone composed of protein that that is produced by the cows pituitary gland
Helps control the production of milk by assisting the regulation of nutrients into the production of milk or fat
BST
Supplementary BST causes the cow to produce less fat and more milk
By splicing genetic material into E. coli bacteria the hormone can be produced at relatively low cost
Genetic AlterationsGenetic Alterations
Genetic engineering doesn’t have to be completed in a lab.
Some other ways to genetically alter genes are:Controlled Breeding
Changing the hereditary characteristics of offspring by selecting parents
Inbreeding
Breeding of phenotypically similar individuals
May eventually produce weaker organisms
Increases the chances of harmful homozygous recessive traits
Hybridization
Cross breeding two different but related individuals
Hybrid vigor – individual out-produces its parents
Decreases the chances of harmful homozygous recessive traits
Artificial Insemination
Placing sperm into the female reproductive tract by means other than natural mating.
Embryo Transfer
The transfer of fertilized egg(s) from a donor female to one or more recipient females
Cloning
The production of an exact genetic copy of an organism
MistakesMistakes
Sometimes, chromosomes break, leading to 4 types of changes in chromosome structure:DeletionDuplicationTranslocationInversions
Cell Changes
Mutation – A change in the DNAAffects the production of proteins and
gives a new phenotype
Cell Changes
Chromosome Mutations – change the structure of the chromosome
Occur during cell division
Cell Changes
DeletionA portion of one chromosome is lost
during cell division. That chromosome is now missing certain genes. When this chromosome is passed on to offspring the result is usually lethal due to missing genes.
Cri du chatCri du chat
Wolf-Hirschhorn Wolf-Hirschhorn SyndromeSyndrome
Cell ChangesCell Changes
DuplicationIf the fragment joins the If the fragment joins the
homologous chromosome, then that homologous chromosome, then that region is region is repeatedrepeated
Fragile XFragile X
Cell Changes
Inversion – piece of chromosome breaks and reattaches itself in reverse
Cell Changes Translocation
Broken piece attaches to a different chromosome
A fragment of a chromosome is moved ("trans-located") from one chromosome to another - joins a non-homologous chromosome.
The balance of genes is still normal (nothing has been gained or lost) but can alter phenotype as it places genes in a new environment.
Can also cause difficulties in egg or sperm development and normal development of a zygote.
"Philadelphia chromosome" "Philadelphia chromosome" Translocation 9:22 Translocation 9:22
Acute Acute MyelogenousMyelogenous Leukemia Leukemia
Cell Changes
Non-Disjunction Chromosome pair fails to separate during
meiosis Trisomy
Downs Edwards Patau
Monosomy Turners
Polyploidy Plants
Downs Syndrome Downs Syndrome BoyBoy
47,XY,+2147,XY,+21
Gene Changes
Gene Mutations – involve a single nitrogen base within a codon
Point Mutation – substitution, deletion, or addition of a base
Frame-Shift Mutation – the addition or deletion of a base
Causes the gene to be read out of order
Gene Changes
Mutagens – environmental factors that damage DNA
Examples – Cigarette Tars RadiationAsbestosUV Light
Chromosome Changes
Chromosome Map – diagram of where genes are on a particular chromosome
Crossing Over – parts of genes become rearranged during meiosis
The closer genes are on a chromosome, the less likely crossing over will occur
Chromosome Changes
Electrophoresis – separation of segments of DNA by electricity based on their size
Enzymes cut DNA at a specific base sequence
The shorter the pieces, the further they travel in the gel
Gel ElectrophoresisGel Electrophoresis
Chromosome Changes
DNA Fingerprinting – the use of electrophoresis to determine matches in DNA
Why map chromosomes?
Human Genetics
More difficult to study than other organisms because it takes 75 years to produce 3 generations of humans
Population Sampling
Use a small number of individuals to represent the entire population.
Twins
Use identical twins to distinguish between environmental and hereditary factors
Pedigree Studies
Use family history to determine how a trait is inherited
Carrier – heterozygous – does not have the trait, but may pass it on to offspring
Pedigree Symbols
Male FemaleAffected maleAffected femaleMating
Pedigree Symbols
Parents
Siblings
Known heterozygote for recessive allele
Death
Pedigree Symbols
Fraternal twins Identical twins
Unknownphenotype
??
Female carrier of an x-linked trait
Male at risk
Female at risk
Dominant PedigreesDominant Pedigrees
Ear Lobe Attachment
Unattached is dominate (F) to Attached (ff)
Ear Lobe Attachment
Ear Lobe Attachment Example
1
1
1
1
2
2
2
2
3
3
4
4 5 6
3 4 5 6 7 8
Ear Lobe Attachment Example
I
II
III
IV
1
1
1
1
2
2
2
2
3
3
4
4 5 6
ff ff
ff
ff
ff
1 2
ff ff
ff3 4 5 6 7 8
ff ff
Ear Lobe Attachment Example
Unattached earlobes have one Dominant allele
I
II
III
IV
1
1
1
2
2
2
3
3
4
ff ff
ff
ff
ff
F_
ff
F_
F_F_F_
F_
F_
F_
1 2F_
ff ff
ff
F_
3 4 5 6 7 8
ff
21 4 5 6
Ear Lobe Attachment Example
Because the father is recessive the children have to be heterozygous
I
II
III
IV
1
1
1
1
2
2
2
2
3
3
4
4 5 6
ff ff
ff
ff
ff
F_
ff
F_
FfFfFf
F_
Ff
F_
1 2F_
ff ff
ff
F_
3 4 5
ff
7 8ff
Ear Lobe Attachment Example
Because the children are recessive the mother is heterozygous
F_I
II
III
IV
1
1
1
1
2
2
2
2
3
3
4
4 5 6
F_
ff ff
ff
ff ff
ff
ff
ff
F_F_
ff
F_
FfFfFf
Ff
Ff
ff
3 4 5 6 7 8
Recessive PedigreesRecessive Pedigrees
Hints: 1. Individual with the trait has two normal parents
2. Two affected parents can not have an unaffected child
Human Genetic Traits
Single Allele Traits:Dominant – Huntington Disease,
Dwarfism, Polydactyly (extra fingers and toes)
Recessive – Albinism, Cystic fibrosis
Human Genetic Traits
Polygenic Traits:SkinHair and Eye ColorFoot SizeHeightNose Length
Human Genetic Traits
Multiple-Allele TraitsABO blood groupsRh Factor in Blood
Human Genetic Traits
Sex Linked TraitsColor-blindnessHemophiliaMuscular Dystrophy
Human Genetic Traits
Sex-Influenced Traits:Baldness
Human Genetic Traits
Nondisjunction:Down SyndromeKleinfelter SyndromeTurner Syndrome
Detecting Genetic Disorders
Karyotype The grouping of the chromosomes based
on size and the position of the centromere
Amniocentesis The process of removing fluid and cells
from around the fetus and checking for abnormalities
Classification of ChromosomesClassification of Chromosomes
NormalNormalFemale Female KaryotypeKaryotype
NormalNormalMale Male KaryotypeKaryotype