HGProject GM Foods

8/2/2019 HGProject GM Foods

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Discuss how the outcomes of the Human

Genome Project are being used in thedevelopment of new drugs & the social,

moral and ethical issues this raises.

5.8.19

Syllabus Reference:





The Human Genome Project (identifying the complete sequenof code in human DNA) has initiated a new field of medicine capharmacogenetics - the idea that drugs can be targeted at / tailored for individuals based on their DNA.

This would allow:

1) Correct / lower dosages to be used (costs less and fewer sideffects - e.g. cytochrome P450 gene)

2) Ability to choose drugs that work best for individuals (e.g.

common painkillers are more effective for pale skinned, red-hawoman; ibuprofen does not work as well during 2nd half ofmenstrual cycle)

3) Ability to avoid drugs that won’t work in individuals - e.g. kapopioids (pain killers) work better on women than men.

4) Ability to avoid drugs that would give adverse reactions (wousave lives and money)



Pharmacogenomics example now in use:

Cy tochrome P450 gene

·This is a gene that codes for liver enzymes which breakdown drugs so that they can be eliminated from the body

·Gene variations mean some individuals have less P450and are so are vulnerable to drug overdoses.

·Genetic tests can check the P450 gene variation anindividual has, so that the correct dosage can be given.



.8.11

There is a need to consider the social, moral & ethical ssues of HGP & pharmacogenomics:

Pharmacogenomics:

1) Identifying the correct genes is time consuming andcostly- is the potential benefit worth the cost?2) Is it ethical to leave people with certain genetic variatiowithout a particular treatment or drug?3) Is it worth the financial implications in further training fodoctors?

4) DNA databases will need to be analysed and stored - isethical to use these for criminal investigations / immigratiossues?

Human Genome Project:

5) Can you patent / copyright DNA when you sequence it?6) Who should have access to your genetic code?7) Should genetic information be kept on record?8) What if we identify “genes” for intelligence, sexuality, crime?9) Eugenics (i.e. selective breeding in humans) - is this ethical?



Describe how drugs can be produced

using GM organisms (plants, animals micro-organisms).

5.8.20

Syllabus Reference:



GMPlantcrops

Soya Bean PlantsHave been made

herbicide resistant, sothey can be sprayed

without beingaffected.

MaizeHas been modified to

protect against thecorn borer using

bacteria(see next slide)

Flavr Savr Tomatoeshave been modified tslow down the ripenin

process, using an'antisense' gene (whic

blocks enzyme geneexpression).

Oilseed Rapehas been GM to

produce adifferent oil,

using a

bacterium calledagrobacterium .

(see next slides



Simplified!!



.8.11

Genetic Engineering:

How to make a transgenic organism (i.e. with DNA fromore than one source)

More Detailed



Risks of Genetic Engineering

- Can have side effects (see below)!- It's very difficult (so LOTS of repeats to get one

working attempt - bad if we're engineering anima- Costly- In crops the genes often 'escape' into other plawhich may lead to immunity and infertility.- Opens door to human GE

- Accidental release of GE organisms into the wiis BAD- GE biological weapons- Religious objection



Electrophoresis

A form of chromatography used to separate

different pieces of DNA on the basis of their lengt



Making human Insulin - using transgenicmicro-organisms

·Type 1 & 2 diabetessufferers need regularinsulin injections

·Used to come fromanimals such as pigsand cows

·Now micro-organisms can be used tomanufacture insulin (aka 'humulin').

·This can be cultured in huge numbers,though downstream processing is used

separate the end product from the mixture



Human Insulin production - how it works:







GM Microbes - Banana Vaccines

·Plants (such as bananas or carrots) can GM to carry vaccines to human diseases,e.g. diarrhoea or hepatitis B.·Plants can be regrown by communities,cheaply and easily.·Plants do not need a cold storage

·No need for trainedHealthcare workers

·No need for needleinjections.



As well as using a plasmid, thereare other ways of introducingnew DNA into a eukaryotic cell:

Different vectors may be used:

) Harmless viruses - used to infect the animal cell.

Making Transgenic Animals -

Getting the DNA in!

2) Liposome wrapping - inserted gene is wrapped in a liposome

which fuses with the cell membrane to deliver the DNA.

3) Microinjections - DNA is injected into the cell usinfine micropippette. Used to produce 'Tracey' - the

transgenic sheep.

4) Microprojections - using a gene gun - DNA is attato tiny gold pellets and fired into the cell using compressed air.



Making Transgenic Animals -

Microprojections

1) Coat gold particleswith DNA vectors.

2) Load onto a pellet

3) Load pellet into agene gun

4) Shooting the genegun releases theparticles at a high

velocity, penetratingthe cells.



Drugsfrom transgenic

animals

Blood Factor VII & IX

Important for blood clotting.Help haemophiliacs.

Harvested from transgenic milk

AATHigh yields from

transgenic sheep.Help to treat

genetically linkedemphysema & CF

Activated protein CUsed for treating

DVT

Activated

protein CProduces

modified milkfor lactose

intolorencesufferers



Tracey - the Transgenic Sheep

·1991 - Tracey the 1st transgenic sheep w

born, after the gene alpha-1-antitrypsin(AAT) had been inserted into her DNA.·Tracey produced the human protein AAT her milk.·Tracey's milk can be harvested & purifiedextract AAT & given to people without theAAT protein (suffering from lung & liverconditions causing emphysema).



'Pharming'

Facts

Using transgenic animals is sometimes

called 'Pharming'Such methods gave rise to Dolly the sheethe first clone)Research is under way to grow human

organs (such as kidneys) using living pigs.The animals used are like 'living factories'or human proteins or organs.



www.mnn.com/green-tech/research-innovations/photos/12-bizarre-examples-of-genetic-engineering



Discuss the risks and benefits

associated with the use of GMorganisms.

5.8.21

Syllabus Reference:



ow to make a transgenic organism (i.e. with DNA fromore than one source)

Cut required gene out ofonor cell DNA (using a

estriction enzyme).

Separate gene fromther fragments of DNAsing electrophoresis &

gene probeomplementary to the gene

Extract the gene from the gel and copy it using PCRPolymerase Chain Reaction - allows many copies ofNA to be made from a small sample)

Extract plasmids from bacteria (macerate & centrifuge

Cut plasmids open using the same restriction enzyme

Insert the gene into plasmid and seal with DNA Ligasnzyme

Use a vector to get the transgenic plasmid back into aacterium (vector is usually heat shocked)



Benefits of Genetic Engineering

- Can manufacture desired protein easily (e.g.Insulin)- Most proteins can't be made synthetically- Treatment of diseases- Low running costs (after initial cost of makingGE organism).- Renewable- New technology available (e.g. body armourmade from spider’s silk produced by GEgoats)







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