genetically modified organisms
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Transcript of genetically modified organisms
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 breadingSelective 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 HIVº Huntington’s disease DISADVANTAGES
Expensive Difficult Breeding problem
TOPICAL MICROBICIDES FOR BLOCKING HIV-1 TRANSMISSION
Lactobacilli or E. Coli altered to secrete or express proteins with anti–hiv-1 activity
Colonization of the vagina or rectum with recombinant bacteria
Secret fusion inhibitory peptides or proteins
Lactobacilli that maintains a low vaginal ph
Lowers the risk of hiv-1 infection
GENETICALLY MODIFIED PIGS
MEDICINEº Production of pharmaceuticals (human
hemoglobin in blood of pigs for treating Trauma patients)
º Organs for Xenotransplantation into humansº development of models for human diseases
AGRICULTUREº resistance to diseaseº Altering the carcass compositionº Improving pig’s resistance to heat stressº Protecting environment
PIGS GIVEN SPINACH GENES
World's first to genetically engineered mammals to contain DNA from plants
Produce pork that is healthier normal pigs
Produces less fat than normal ,less fat intake
“It is confirmed for the first time in the world that a plant
gene is functioning properly in a living mammal, not in a
cultured cell,” said professor by akira
PIGS GIVEN SPINACH GENES-EXPERIMENT
Inserting the spinach gene into a fertilised pig egg
Implanted in a female pig's womb
FAD2 gene converted about a fifth saturated fatty acids into linoleic acids
ADVANTAGES OF PIG‘SPhysiology and size
Raised in pathogen free condition
Less chance to transmit infectious disease to humans
Have fewer ethical issues as donor
Short generation interval(114 days)
Genome is quite similar to humans (3x times than mouse)
GOAT THAT PRODUCE SPIDER SILKTwo 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
The challenge : how they take a powder and spin it into a fibre,
like a spider does?
The two proteins are combined into a solution
Transformed into microfibers using wet-spinning fibre production methodologies
"Biosteel biopolymer" had been transformed into nanofibres and nanomeshes using electro spinning technique
WAYS GMO TOXICITY AFFECTS ANIMALS, PLANTS AND SOIL
Cancer
Damage native species
Pollute the environment
Deplete soil minerals, destroy beneficial bacteria
'Super weeds,' 'superbugs.'
Cause infertility, stillbirths, miscarriages
LAB ANIMALS TESTED WITH GM FOODS
Stunted growth
Impaired immune systems
Bleeding stomachs
Impaired blood cell development
Misshapen cell structures in the liver, pancreas, and testicles
Altered gene expression and cell metabolism
Their offspring have a lower chance of survival
Higher blood sugar
Enlarged livers, pancreases
Inflamed kidneys
Less developed brains and testicles
Intestines reduced digestive enzymes
The animal’s life spans are shortened
Inflamed lung tissue
ADVERSE EFFECTS OF GMO’S
Already 37 people have died from side effects
1,500 partially paralyzed
5,000 were temporarily handicapped by chemicals used in harvesting
Glyophosate "caused malformations in frog and chicken embryos "
Malformations of the head
Increased death rates and higher offspring mortality
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
QUERIES…..????