DNA Technology Notes. Genetic Engineering Genetic Engineering – making changes in the _________...

DNA Technology Notes

Genetic Engineering – making changes in the _________ code

DNA Manipulation:1.Cells are opened and the DNA is _____________ from other cell parts

2. Biologists cut the DNA into smallerfragments using _________________ ___________ which cut the DNA at a specific sequence of ______________

Gel Electrophoresis3. Using _________________, a mixture of DNA

fragments is placed at one end of a porous gel. When electric voltage is applied, DNA (negatively charged) move toward the positive end of the gel. The smaller the DNA fragment, the ______ and ______ it moves!

DNA fingerprinting

Can you determinewho the father is?

CSI: Who is the Dad?

Can you determinewho the father is?

DNA Fingerprinting and Endangered Species

• DNA can identify endangered or protected animals.

• The DNA from endangered animals has been preserved in banks.

• For example, DNA from grizzly bears has been banked to help these declining animals preserve a healthy genetic pool.

Cell Transformation- Transforming Bacteria (____________________)

During __________________, a cell takes in DNA from outside the cell. This external DNA becomes a component of the cell’s DNA.

Free DNA

TransformedBacterium

Plasmid + DNA

BacteriumPlasmid

Cell Transformation

In bacteria, the circular DNA molecule is known as a ________________.

Plasmid DNA has two essential features:1. Its DNA sequence helps promote plasmid __________________.2. If the plasmid containing the ________ DNA manages to get inside a ___________ cell, this sequence ensures that it will be ___________.

Bacterial Transformation

Why is Transforming Bacteria Important?

When organisms contains genes from another species, they are called __________________.

Transgenic bacteria now produce important substances useful for _________ and industry.

These transformed bacteria produce proteins cheaply, ____________, and abundantly.

Examples are human insulin for people with _______________, growth hormones and clotting factor for people with ____________.

Examples of Other Transgenic Organisms (Genetically Modified Organisms):

Transgenic Animals- laboratory mice have been produced with human genes to that their immune systems are similar to humans. This way scientists can study human ___________ by using mice. Some livestock have extra copies of growth hormone genes which allows them to grow _______ and have _____ meat.

Gene causes these mice to glow in the dark. Normally, the gene is found in jellyfish.

How Did They Do That?

1. The jellyfish has a gene that makes a glowing protein. This makes the jellyfish glow in some types of light.

2. The glowing gene is taken from a jellyfish cell and spliced (inserted) into an empty virus cell (with no bad virus in it)

3. The genetically engineered virus attaches itself to the fertilized mouse egg cell.

4. The virus delivers the glowing gene into the egg cell nucleus, where it joins the mouse DNA.

5. The genetically engineered mouse egg grows into an adult mouse which will make the glowing protein. The glow is too faint to see under normal lights but can be detected using a special camera.

Virus

Jellyfish cell

Mouse cell

Virus inserting their DNA into a cell

What’s Been Done So Far?

• Genetically engineering chickens so they have no feathers – why?

• Genetically engineering mice so they have no fur – why?

• Genetically engineering salmon (fish) so they grow much faster than normal salmon – why? http://www.exn.ca/Stories/2000/04/11/61.asp

• Glowing mice

Examples of Other Transgenic Organisms (GMO’s):

Transgenic PlantsPlants can contain genes that produce a natural

______________ so that plants do not have to be sprayed.

In the future, plants could produced human __________________to help fight diseases.

This diagram shows how one type of GM food, a strawberry that resists frost damage is made. The flounder is a fish that live in icy seas. It has a gene that stops it from freezing to death.Strawberries are soft fruits that can easily be damaged by frost.

1. The flounder’s ________ gene is copied and inserted into a small ring of DNA taken from a bacteria cell.

2. The DNA ring containing the flounder gene is put into a second bacterium.

3. This second bacterium is used to infect the strawberry cell. The flounder’s antifreeze gene enters the ____________ DNA. Strawberry cell

with Antifreeze gene4. The new GM

strawberry cell is grown into a GM strawberry plant which can be bred many times.

Thanks to the new gene, GM strawberries make a protein which helps them resist __________. They don’t contain any other fish genes and, and do not taste or smell of fish.

Wonder what they used to make this one green!

Examples of Other Transgenic Organisms:

A rice plant has been developed to contain ____________, a nutrient that is essential for our health. Rice is a major food source for billions of the world’s population

What Have I Eaten?Genetically modified (GM) foods possess specific traits such as tolerance to ______________ or resistance to ____________ or ________________.

By most estimates, up to 70% of the processed foods at your local grocery store contain at least one ingredient that’s been genetically altered

Genetically modified to reduce being eaten by insects.

Genetically modified to travel better so don’t have to be picked when green – better tasting!

ClickClick

GMO food list

How can we use genetically engineering to help us?

By inserting a gene for human insulin into an E.Coli bacterium, the E. coli will make lots of insulin, which scientists and doctors can collect and use.

Right now, doctors are using pig hearts for transplants but there are still rejection problems. One day soon, scientists will be able to genetically engineer pigs to grow human organs for use in transplants.

Pros and Cons of GMO’sCrops • Better taste and quality • Less time to ripen.• More nutrients, more food, and stress tolerance • Improved resistance to disease, pests, and

herbicides • New products and growing techniques Animals • Increased resistance, productivity, hardiness, and

feed efficiency • Better yields of meat, eggs, and milk • Improved animal health and diagnostic methods Environment • "Friendly" bioherbicides and bioinsecticides • Conservation of soil, water, and energy • Better natural waste management • More efficient processing Society • More food for growing populations

Safety • Potential human health impact: allergens, transfer

of antibiotic resistance markers, unknown effects • Potential environmental impact: unintended

transfer of transgenes through cross-pollination, loss of flora and fauna biodiversity

Access and Intellectual Property • Domination of world food production by a few

companies • Increasing dependence on Industralized nations by

developing countries Ethics • Violation of natural organisms' intrinsic values • Tampering with nature by mixing genes among

species • Objections to consuming animal genes in plants and

vice versa • Stress for animal Labeling • Not mandatory in some countries (e.g., U. States) • Mixing GM crops with non-GM confounds labeling

attempts

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Human Genome Project

• Started in _____________• Research effort to ________________ all of

our _________ (46 chromosomes)• Over _______ billion nucleotides• Mapping every ________ _________(loci)• Conducted by scientists around the world

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Benefits of Human Genome Project

• Improvements in Improvements in __________ __________ ______________________________ of disease, of disease, gene therapies, diagnosis gene therapies, diagnosis techniques …techniques …

• Production of useful Production of useful ________________________ products for products for use in medicine, agriculture, use in medicine, agriculture, bioremediation and bioremediation and pharmaceutical industries.pharmaceutical industries.

Gene TherapyGene Therapy- an absent or ___________ gene

is replaced with a normal, ___________ gene.

Gene TherapyIn gene therapy, ______ are often used because

they have the ability to enter a cell’s DNA. The virus particles are modified so that they

cannot cause _______. Then, a DNA fragment containing a replacement gene is __________ to the viral DNA.

Virus

Gene Therapy

The patient is then infected with the modified virus particles, which should carry the gene into _____ to correct the genetic defects.

Unfortunately, these experiments have not been very successful.

Gene therapy remains a ________, experimental procedure.

Cystic Fibrosis and Gene Therapy

What is Gene Therapy?1. In people with cystic

fibrosis, one of the genes is faulty and cannot do its job properly.

2. To fix the problem, a copy of the same gene from a healthy person is spliced into a virus.

3. The patient’s lungs are infected with the virus. It delivers the working gene into the patient’s cells. The cells can then make the right protein, and the patient can breathe normally.

Patient’s cellPatient’s DNAFaulty Gene

Virus DNANew working gene

Patient’s DNAVirus DNA with new gene

Severe Combined Immunodefiency(aka “Bubble Boy”)

In 1990, SCID was the first illness treated by gene therapy.

The normal gene was transferred into the defective white blood cells to compensate for the genetic mutation.

CloningA clone is a member of a population of

genetically identical cells produced from a single cell.

Researchers hope that cloning will enable them to make copies of transgenic animals to help save endangered species.

How to Clone a Sheep

Cloning a Human

CloningThis technology is controversial because some

studies suggest that cloned animals may suffer from genetic defects and health problems.

Cloning in humans raises serious ethical and moral issues.

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