genetically modified organisms

What are GM’s?

Organism one that has been altered through

recombinant DNA technology

Involves either the combining of DNA from

different genomes or the insertion of foreign DNA

into a genome

The most common genetically modified (GM)

organisms are crop plants

Microbes are the first organisms to be genetically

modified

Other terms that mean the

same thing:

Genetically engineered

Transgenic

Recombinant DNA (rDNA) technology

What is not a GMO?

Does not include

Mutants.

Fusion of animal cells unless the product can form an

animal.

Plants formed x protoplast fusion.

Plants formed by embryo rescue or invitro fertilisation or zygote implantation.

Organisms formed by natural DNA transfer.

How does this differ from

Mendel and his peas?GM vs. Selective breading

Selective breading

Slow

Imprecise

Modification of genes that naturally occur in the organism

Occur between plant/animal of same species(dog dog)

GM

Very fast

Precise

Can introduce genes into an organism that would not occur naturally

It can occur between different types of species

(Human bacteria)

How transgenic organisms

work…Three Main Methods…

DNA Microinjection

A foreign gene is directly injected into a fertilized egg that is put into a female animal that acts as a surrogate mother for the egg.

Retrovirus-Mediated Gene Transfer

A retrovirus is a virus that attaches to an organism’s DNA and changes it to include a new characteristic. Scientists expose ordinary cells to a retrovirus when they are trying to create transgenic animals.

Embryonic Stem Cell-Mediated Gene Transfer

Stem cells are blank cells that can turn into any type of cell. Scientists modify these cells, and then add them to an embryo, which is a fertilized egg that develops and grows until it hatches or is born.

DNA MICROINJECTION

Most commonly used

method

Only 5% or less of the

treated eggs become

transgenic progeny

Need to check mouse

pups for DNA , RNA and

protein ( by some

specific assay method)

Expression will vary in

transgenic offspring:

due to position effect

and copy number

Figure 1.1

Figure 1.2

Less than 5% of the microinjected fertilized eggs become

transgenic progeny

Figure 21.1

Retroviral vectors

can be used to

create transgenic

animals

RETROVIRUS-MEDIATED GENE

TRANSFER

Figure 1.4

Genetically

engineered

embryonic stem (ES)

cells can be used to

create transgenic

animals

This method allow for

gene targeting via

homologous

recombination.

EMBRYONIC STEM CELL-

MEDIATED GENE TRANSFER

GENETICALLY ENGINEER OF THE ES CELLS

Figure 1.5a

GENETICALLY ENGINEER OF THE ES CELLS

Figure 1.6b

THE TWO MOST COMMON TYPES OF GMO’S

I. FOODS

Crops are modified to develop resistance to

herbicides and increase their nutrient

content, for example corn and soybeans .

Fruits are modified to make them ripen later.

This help them available fresh in marketplace

during a longer time or for fruits that ripen

after being picked, make it easier to

transport them.

THE TWO MOST COMMON TYPES OF

GMO’SII. MEDICINES

These can be produced cheaper and easier

some are: insulin, thyroid hormones and the

Hepatitis B vaccine

GM Bacteria’s have been particularly important in

producing large amounts of pure human proteins

for use in medicine like clotting factors for

hemophilia and human growth hormones to treat

dwarfism

OTHER TYPES OF GMO’S ARE

III. MAMMALS

Research human diseases

(To develop animal models for many diseases.)

Produce industrial or consumer products

(pharmaceutical products or tissue implantation)

Enrich the animals’ interactions with humans

(Hypo-allergic pets)

Enhance production or food quality traits

(faster growth fish, pigs that digest food more

efficiently)

Improve animal health(disease resistance)

OTHER TYPES OF GMO’S AREIV. INSECTS

The effects of genetic changes on development

(malaria resistant mosquitoes)

V. AQUATIC LIFE

Evolution of immunity and developmental processes,

rapid growth

( MADAKA -fish to detect pollutions in waterways)

TRANSGENIC MONKEY

Its so similar to human hence it used in

clinical trail used for studying :

º HIV

º Huntington’s disease

DISADVANTAGES

Expensive

Difficult

Breeding problem

GOAT THAT PRODUCE SPIDER SILK

Two key genes that allow a spider to weave their silk inserted into their genetic code.

That produce milk that contain spider silk proteins

Proteins are then harvested through the goat's milk

Goats are separated into two groups, each contains one of the two proteins

Proteins must be extracted and combined

GOAT THAT PRODUCE SPIDER SILK

Stronger than steel and

more flexible

Used to replace

damaged tendons and

ligaments , suture

damaged eyes, or even

nerves

Make stronger and safer

parachutes for soldiers ,

bulletproof vests

SILK FROM MILK

Goats are milked

Milk is frozen and the cream is separated

Thawed milk is pushed into a micro filter that

blocks the larger fat molecules and lets the

smaller proteins through

A smaller filter then further isolates the silk

proteins

When dried looks like a white powder

CURRENT RESEARCH

Mosquito-borne diseases remain one of the greatest global threats to human health

With recombinant and novel combinations of DNA passing into the environment

Effects of gm plants on soil processes such as decomposition

Lactococcus lactis secreting interleukin 10 provides a therapeutic approach for inflammatory bowel disease

CONCLUSION

Transgenic animals are now-a-days used for

screening of many drugs

Using of transgenic animals reduce number of

experimental animals during testing

We will need them in the future