DNA Technology

I. Genes in action

• Mutation – Change in structure or amount of genetic material of an organism. Change in DNA sequence.

* Most genetic differences result from some kind of genetic mutation.

Ex. brown vs blue eye color

Mutagens

• Environmental factors which increase mutation rates. Include forms of radiation and some kinds of chemicals

Ex: UV radiation and skin cancer, Cigarette smoke and lung cancer

Results of Genetic Change

1) Harmful – Sickle cell, Tay-Sachs, Cystic Fibrosis

2) Beneficial - Larger crops, resistance to pesticides

3) Neutral – No change in organism*

* most common

Results of Genetic Change

1) Harmful – Sickle cell, Tay-Sachs, Cystic Fibrosis

2) Beneficial - Larger crops, resistance to pesticides

3) Neutral – No change in organism*

* most common

Sickle Cell Anemia

Tay-Sachs Disease

2 Types of Mutations

1) Somatic cells (Body cells)– Ex: Cancer, tumors,

warts

2) Germ cells (Gametes) *

* Only mutations in Germ cells (gametes) can be inherited

II. Gene Technology

• Genome – All the DNA an organism has within its chromosomes

• Human Genome Project – Identified all the human genes on each of the 46 chromosomes

A) Genetic Engineering

• Genetic Engineering The deliberate change of genetic material of an organism. Copies of a gene from one organism are inserted into another

The presence of a fluorescent component in the bioluminescent organs of Aequorea victoria jellyfish

The presence of a fluorescent component in the bioluminescent organs of Aequorea victoria jellyfish

Recombinant DNA

• Recombinant DNA is DNA that has been recombined by genetic engineering.

• New organisms are called recombinants, transgenics, or GMO’s (genetically modified organisms)

A tobacco plant that has been genetically engineered with a fluorescent gene that causes it to glow...

A tobacco plant that has been genetically engineered with a fluorescent gene that causes it to glow...

Recombinants, transgenics, or GMO’s (genetically modified organisms)

Genetic Engineering process:

1) Restriction enzymes cut DNA samples from an organism’s chromosome and bacterial plasmid.

2) The two DNA are spliced together with a special ligase enzyme.

Genetic Engineering process:

1) Restriction enzymes cut DNA samples from an organism’s chromosome and bacterial plasmid.

2) The two DNA are spliced together with a special ligase enzyme.

Genetic Engineering process:

1) Restriction enzymes cut DNA samples from an organism’s chromosome and bacterial plasmid.

2) The two DNA are spliced together with a special ligase enzyme.

Genetic Engineering process:

3) The recombinant DNA plasmid is placed in a host bacteria

4) When the bacteria reproduces and divides the “new” gene is present

Genetic Engineering process:

3) The recombinant DNA plasmid is placed in a host bacteria

4) When the bacteria reproduces and divides the “new” gene is present

Genetic Engineering process:

3) The recombinant DNA plasmid is placed in a host bacteria

4) When the bacteria reproduces and divides the “new” gene is present

Genetic Engineering application

• Food crops, livestock, medical treatment (insulin), basic research

The presence of a fluorescent component in the bioluminescent organs of Aequorea victoria jellyfish

http://upload.wikimedia.org/wikipedia/commons/f/f2/GloFish.jpg

B) DNA fingerprinting

Process:• 1) A collected DNA

sample is cut into fragments using restriction enzymes.

• 2) Special polymerase enzymes create several batches of the sample DNA

B) DNA fingerprinting

Process:• 1) A collected DNA

sample is cut into fragments using restriction enzymes.

• 2) Special polymerase enzymes create several batches of the sample DNA

B) DNA fingerprintingProcess:• 3) The DNA fragments

are sorted by an electrical impulse technique called gel electrophoresis

• 4) Exposure to photographic or X-ray film reveals the single strands. Each person’s DNA makes a unique pattern

B) DNA fingerprintingProcess:• 3) The DNA fragments

are sorted by an electrical impulse technique called gel electrophoresis

• 4) Exposure to photographic or X-ray film reveals the single strands. Each person’s DNA makes a unique pattern

B) DNA fingerprintingProcess:• 3) The DNA fragments

are sorted by an electrical impulse technique called gel electrophoresis

• 4) Exposure to photographic or X-ray film reveals the single strands. Each person’s DNA makes a unique pattern

DNA fingerprinting

• Application:• DNA fingerprints can

be compared to determine if samples are from the same person or related ancestry. Used to ID criminals, family members, deceased bodies

DNA fingerprinting

• Application:• DNA fingerprints can

be compared to determine if samples are from the same person or related ancestry. Used to ID criminals, family members, deceased bodies

It is easy to see in this example that daughter 2 is the child from the mother’s previous marriage and son 2 is adopted. You can see that both daughter 1 and son 1 share RFLPs with both the mom and dad (coloured blue and yellow respectively), while daughter 2 has RFLPs of the mom but not the dad, and son 2 does not have RFLPs from either parent.

C) Cloning

• Cloning – An organism or piece of genetic material that is identical to the original or parent organism. Process where a single cell becomes a whole identical organism

Fig. 20-16

EXPERIMENT

Transversesection ofcarrot root

2-mgfragments

Fragments werecultured in nu-trient medium;stirring causedsingle cells toshear off intothe liquid.

Singlecellsfree insuspensionbegan todivide.

Embryonicplant developedfrom a culturedsingle cell.

Plantlet wascultured onagar medium.Later it wasplantedin soil.

A singlesomaticcarrot celldevelopedinto a maturecarrot plant.

RESULTS

Fig. 20-17

EXPERIMENT

Less differ-entiated cell

RESULTS

Frog embryo Frog egg cell

UV

Donornucleustrans-planted

Frog tadpole

Enucleated egg cell

Egg with donor nucleus activated to begin

development

Fully differ-entiated(intestinal) cell

Donor nucleus trans-planted

Most developinto tadpoles

Most stop developingbefore tadpole stage

                                                                                                                                                 

                                 

Fig. 20-18

TECHNIQUE

Mammarycell donor

RESULTS

Surrogatemother

Nucleus frommammary cell

Culturedmammary cells

Implantedin uterusof a thirdsheep

Early embryo

Nucleusremoved

Egg celldonor

Embryonicdevelopment Lamb (“Dolly”)

genetically identical tomammary cell donor

Egg cellfrom ovary

Cells fused

Grown inculture

1

33

4

5

6

2

Cloning

• Natural cloning – Asexual reproduction in bacteria, budding of parts in some plants and fungi, vegetative propagation of new plants from parts

Any plans for today?

Yeah! I’m

going

fission!

Hey Bud,

What’s

up?

Not much!

Hey Bud!

What

Spud?

Hi Mom! It’s

me, You!

Any plans for

today?

Yeah! I’m

going

fission!

Hey Bud, What’s

up?

Not much!

Hey Bud!

What

Spud?

Hi Mom! It’s

me, You!

D) Stem cells

• Stem cells – cells that continually divide and form various tissues.

• Found in embryo and some tissues– Application: Can be

used to produce or replace damaged nerve, muscle, blood, or

D) Stem cells

• Stem cells – cells that continually divide and form various tissues.

• Found in embryo and some tissues– Application: Can be

used to produce or replace damaged nerve, muscle, blood, or

D) Stem cells

• Stem cells – cells that continually divide and form various tissues.

• Found in embryo and some tissues– Application: Can be

used to produce or replace damaged nerve, muscle, blood, or