MUTATION– a CHANGE in the DNA

-Affects the production of PROTEINS and gives a new PHENOTYPE

CHROMOSOME MUTATIONS

-Change structure of chromosome . Occur during CELL DIVISION.

-Deletion – piece of chromosome BREAKS off

- Inversion – piece of chromosome breaks and REATTACHES itself in reverse

 -Translocation – broken piece attaches to a DIFFERENT chromosome

- Nondisjunction – chromosome pair fails to SEPARATE during meiosis

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

MUTAGENS

-environmental factors that DAMAGE DNA

Examples – RADIATION

CIGARETTE TARS

ASBESTOS

UV LIGHT

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

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 FARTHER they travel in the gel.

DNA FINGERPRINTING

-The use of ELECTROPHORESIS to determine matches in DNA sequences.

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

HUMAN GENETIC TRAITS

-Single allele traits

Dominant – Huntington Disease, Dwarfism, Polydactyly

Recessive – Albinism, Cystic fibrosis

Polygenic traits

Skin, hair and eye color

Foot size, Height, Nose length

Multiple-allele traits

ABO blood groups

Rh factor in blood

Sex Linked Traits

Color-blindness

Hemophilia

Muscular Dystrophy

Sex-Influenced Traits

Baldness

Nondisjunction

Down Syndrome, Kleinfelter

Syndrome, Turner 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

Applied Genetics

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

Genetic Engineering

The ability to move genetic material (genes) from one organism to another

Steps in Genetic Engineering

Isolate the gene and cut it using restriction enzymes

Cut bacterial DNA using restriction enzymes

Splice the gene into bacterial DNA by attaching “sticky” ends

Steps in Genetic Engineering

Place the engineered bacterial DNA into a bacteria cell

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 mice

3. Map the human genome

4. 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 Insulin

2. Human Growth Hormone

3. BST

4. TPA -- clot dissolving formula

5. Vaccines

Artificial Insemination

Placing sperm into the femalereproductive 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