NOTES:

IS THIS FOR REAL?• What are the

advantages?

• What are the

disadvantages?

• Is it right to create

an animal like this

simply to make

our lives easier?

GENETIC ENGINEERING• IS THE PROCESS OF MAKING

CHANGES TO DNA IN ORDER TO

CHANGE THE WAY LIVING

THINGS WORK.

• CREATES NEW CROPS AND FARM

ANIMALS.

• MAKES BACTERIA THAT CAN

PRODUCE MEDICINES.

• CAN GROW HUMAN BODY PARTS.

• CAN PREVENT GENETIC DISEASES,

CHANGE HUMANS.

ALTERING ORGANISMS ISN’T NEW, WE’VE BEEN DOING IT FOR 1000’S OF YEARS…

IT’S CALLED - SELECTIVE BREEDING.

SELECTIVE BREEDING IN DOGS

RECENT PRODUCT OF SELECTIVE BREEDING: THE LABRADOODLE

• CROSSING A POODLE AND A LABRADOR RESULTS IN A

‘LABRADOODLE’

• WHAT FEATURES HAS THE LABRADOODLE INHERITED FROM THE

LABRADOR?

• WHAT FEATURES HAS THE LABRADOODLE INHERITED FROM THE

POODLE?

Poodle Labrador Labradoodle

+

+

LABRADOODLE CHARACTERISTICS

• LARGE (LIKE THE LABRADOR);

• FLUFFY COAT (LIKE THE POODLE)

WHICH SHEDS MUCH LESS THAN A

LABRADOR’S COAT.

• LIKE BOTH BREEDS, THEY ARE:

• GENERALLY WELL TEMPERED;

• GOOD SWIMMERS.

• SO THE LABRADOODLE HAS FAVORABLE

CHARACTERISTICS FROM BOTH OF ITS

PARENT BREEDS.

Labradoodle

SELECTIVE BREEDING• IS A PROCESS USED TO PRODUCE DIFFERENT BREEDS OF

ANIMALS OR VARIETIES OF PLANTS THAT HAVE USEFUL CHARACTERISTICS.

• USING SELECTIVE BREEDING YOU CAN PRODUCE A SPECIFIC OFFSPRING WITH USEFUL CHARACTERISTICS OF BOTH PARENTS.

• WHAT ORGANISMS DO FARMERS ‘SELECTIVELY BREED’?

SELECTIVE BREEDING

• FARMERS CAN MATE SPECIFIC COWS IN TO PRODUCE A GENERATION OF COWS THAT WILL YIELD MORE MILK.

• FARMERS COULD ALSO SELECTIVELY BREED FOR DOCILE ANIMALS.

• APPLE GROWERS WANT TO PRODUCE A TYPE OF APPLE THAT IS TASTY AND RESISTANT TO DISEASE. THIS CAN BE DONE BY CROSSING A VARIETY OF APPLE KNOWN FOR TASTE WITH ANOTHER VARIETY THAT SHOWS STRONGRESISTANCE TO DISEASE.

ANOTHER EXAMPLE: DAIRY COWS• IF YOU WANTED A VARIETY OF COW

THAT PRODUCED A LOT OF MILK, YOU

WOULD:

• SELECT THE COWS IN YOUR HERD

THAT PRODUCE THE MOST MILK.

• ALLOW ONLY THESE COWS TO

REPRODUCE.

• SELECT THE OFFSPRING THAT

PRODUCE THE MOST MILK.

• ONLY LET THESE OFFSPRING

REPRODUCE.

• KEEP REPEATING THE PROCESS OF

SELECTION AND BREEDING UNTIL

YOU ACHIEVE YOUR GOAL.

• THE KEY IS TO IDENTIFY THE FEATURE YOU

WANT, AND ONLY BREED THE INDIVIDUALS

THAT HAVE THAT FEATURE:

• SELECT PARENTS WITH THE DESIRED TRAITS.

• CROSS THE PARENTS (BREED THEM).

• SELECT FROM THE OFFSPRING.

• REPEAT OVER MANY GENERATIONS.

• SELECTIVE BREEDING IS USED TO: -

• CHOOSE THE CHARACTERISTICS OF FOOD.

• PRODUCE A MORE UNIFORM CROP:

• SIZE

• HARVEST TIME

• EXTEND THE TOLERANCE RANGE OF AN

ORGANISM.

PERFECT PET

• IMAGINE YOU WANTED TO CREATE YOUR PERFECT DOG – HOW

WOULD YOU SELECTIVELY BREED FOR IT?

• WHAT TWO PARENTS ARE YOU GOING TO CHOOSE?

• WHAT QUALITIES DO EACH OF THEM HAVE (WHICH YOU WANT)

• HOW ARE YOU GOING TO ‘GET’ THESE QUALITIES IN YOUR PET?

HOWEVER, THE TRAITS INHERITED ARE RANDOM &

UNPREDICTABLE.

BUT, WITH GENETIC ENGINEERING:

• TRAITS ARE SELECTED

INTENTIONALLY.

• OFFSPRING RECEIVE

SPECIFIC DNA FROM

PARENTS.

• DESIRED RESULTS ARE

ALMOST ALWAYS

OBTAINED.

The simple

addition, deletion,

or manipulation of

a single trait in an

organism to

create a desired

change.

Genetic Engineering is:

• Major tool of genetic engineering is recombinant

DNA.

• Recombinant DNA (rDNA) - DNA joined to other

unrelated foreign DNA.

– Also called gene splicing.

HOW IS IT DIFFERENT FROM SELECTIVE

BREEDING?

• In selective breeding, we are combining the traits of

two organisms randomly.

• We get a random mixture of their genes, while

hoping for the results we seek.– We might get what we want. But a bunch of other traits

will come along with it.

• In genetic engineering, a single gene, a half page

recipe in the 52-thousand-page set of recipe books,

can direct the plant to make new traits.

• Or it could remove an undesirable trait.

Transgenic Organisms:

Are organisms that have been altered by genetic engineering.

• Genetic material changed by other than random natural breeding.

• Gene transfer -moving a gene from one organism to another.

TYPES OF TRANSGENIC ORGANISMS

• GMO- Genetically Modified Organism.

• Uses genes not found in the organism to provide new

traits.

• GEO - Genetically Enhanced Organism

• Uses superior versions of genes already found in the

organisms genome.

Time for a quick poll:Question #1:

Raise your hand if you would eat food

(plant or animal) that had been created

through genetic modification.

Question #2:

Raise your hand if you would eat

vegetables that had been created

through genetic modification – but NOT

meat.

Question #3:

Raise your hand if you would eat meat that

had been created through genetic

modification – but NOT vegetables.

Question #4:

Raise your hand if you would eat both meat

& vegetables that had been created

through genetic modification.

RESULTS FOR A SIMILAR POLL CONDUCTED IN AMERICA

WHAT ARE GENETICALLY MODIFIED (GM) FOODS? (“Frankenfoods”?)

You have probably already eaten

GM foods. Some GM tomatoes,

for example, have had their

genes altered to stop them from

going soft while they are still

growing. For several years they

were widely sold in tomato paste.

The GM foods we eat have all

been tested for safety. But some

people worry about the long term

effects of eating genetically

modified foods.

WHAT HAVE I EATEN?

Genetically modified (GM) foods

possess specific traits such as

tolerance to herbicides or

resistance to insects or viruses.

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!

SAY GOODBYE TO BANANAS• According to recent reports, the world may

soon be out of bananas.

• Because of it’s unique method of reproduction,

banana plantations in Africa, Asia and Central

America are uniquely susceptible to fungi,

viruses and pests.

• Unless scientists can find a way to genetically

enhance the banana’s ability to ward off

parasites, we could be banana-less in ten

years.

• Several agroscience companies believe they

can genetically engineer such an invincible

banana by copying parts of the genetic codes

of other fruits and instilling them into the

banana.

PROS OF GENETIC ENGINEERING:

• Crops• 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

CONS OF GENETIC ENGINEERING

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

HOW CAN WE USE GEN. ENG. TO HELP PEOPLE?

By inserting a gene for human insulin

into an E.Coli bacterium, the E. coli

will make tons 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.

• Crops given extra genes for new and useful

characteristics are called genetically modified

(GM). What characteristics

might be useful in

crops? pest resistance

frost resistance

herbicide resistance

drought resistance

longer shelf life

disease resistance

GM CROPS

• Potatoes can be genetically modified so they are toxic

to pests, such as the Colorado Beetle.

The gene for a

powerful bacterial

toxin is added to

the potato plant.

If the beetle tries

to eat the potato

plant, it is killed

by the toxin.

PEST-RESISTANT CROPS

Crops can be genetically modified so they are

resistant to adverse environmental conditions.

For example,

lettuces could be

genetically modified

to be resistant to

frost.

GM

lettucenon-

GM

lettuceWhy are some people against the

development and use of GM crops?

FROST-RESISTANT CROPS

• Rice can be genetically modified to make beta-

carotene, a substance that is converted into vitamin

A in the body.

PLANTS WITH EXTRA VITAMINS

• The GM rice is called

‘Golden Rice’ and is

being developed to

help fight vitamin A

deficiency and

blindness in

developing countries.

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 cell

Patient’s DNA

Faulty Gene

Virus DNA

New working

gene

Patient’s DNA

Virus DNA with

new gene

CLONING:

The first animal ever cloned

was a sheep named Dolly.

Now cats can have

more than nine lives.

The company that

funded the first

successful cloning of a

domestic cat, has

gone commercial. You

can clone your own

kitty. Your cost? U.S.

$50,000 each.

Cloning Cats

"Cc," the first cat ever cloned at seven weeks old with Allie, her surrogate

mother.

• Cc was cloned by transplanting DNA

from a female three-colored calico cat

into an egg cell whose nucleus had

been removed.

• Then this embryo was implanted into

Allie, the surrogate mother.

• A genetic match between Cc and the

donor mother confirms they are clones.

MIXING HUMANS AND ANIMALS

• Scientists have begun blurring the line

between human & animal by

producing chimeras—a hybrid

creature that's part human, part

animal.

• In 2003, Chinese scientists at the

Shanghai Second Medical University

successfully fused human cells with

rabbit eggs.

• The embryos were the first successful

human-animal chimeras.

• They were allowed to develop for

several days before the scientists

destroyed the embryos to harvest

their stem cells.

The mythic beast had a lion's

body, serpent's tail, and goat's

head.

• In Minnesota researchers at the

Mayo Clinic created pigs with

human blood flowing through

their bodies.

• At Stanford University in California an experiment

is planned to create mice with human brain

organization. • Scientists feel that, the more humanlike the animal, the

better research model it makes for testing drugs or

possibly growing "spare parts" to transplant into

humans.

For example, the gene for a human antibody

can be introduced into goats.

The antibody is then expressed in the goat’s

milk, where it can be purified and used to treat

diseases.

Additional controlling

DNA is also introduced,

so the human antibody

is only produced in the

goat’s mammary gland

at a certain time.

TRANSGENIC GOATS

WHICH CAME FIRST?

The eggs of this

transgenic chicken

contain a human

antibody that could

one day help to treat

skin cancer.

What advantages

does this method

of producing

antibodies have?

ANDI

• Scientists at the Oregon Regional Primate

Research Center announced the birth of

the first genetically engineered primate,

named ANDi (for "inserted DNA" spelled

backwards).

• ANDi’s cells contain the gene that makes

jellyfish glow in the dark.

• The experiment was something of a flop;

ANDi does not glow.

• THE SPIDER GOAT, FROM THE UNIVERSITY OF WYOMING, WAS ENGINEERED WITH GENES TO PRODUCE SPIDER SILK IN ITS MILK. THIS IS IMPORTANT BECAUSE SPIDER SILK IS INCREDIBLY STRONG, AND HAS BEEN USED IN KEVLAR VESTS.

BOVINE SOMATOTROPIN (BST)

•BST IS A HORMONE COMPOSED OF PROTEIN THAT IS PRODUCED BY THE COWS PITUITARY GLAND.

• IT HELPS CONTROL THE PRODUCTION OF MILK BY ASSISTING THE REGULATION OF NUTRIENTS INTO THE PRODUCTION OF MILK OR FAT.

BST• SUPPLEMENTARY BST CAUSES

THE COW TO PRODUCE LESS

FAT AND MORE MILK.

• BY SPLICING GENETIC

MATERIAL INTO E. COLI

BACTERIA THE HORMONE CAN

BE PRODUCED AT RELATIVELY

LOW COST.

1982

• HUMULIN® IS APPROVED FOR THE TREATMENT

OF DIABETES.

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

antifreeze 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 strawberry’s

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 frost. 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

blue? – A

different gene

from another

organism.

RECOMBINANT DNA• THE ABILITY TO

COMBINE THE DNA OF ONE ORGANISM WITH THE DNA OF ANOTHER ORGANISM.

• RECOMBINANT DNA TECHNOLOGY WAS FIRST USED IN THE 1970’S WITH BACTERIA.

BASIC STEPS OF GENETIC ENGINEERING

• STEP 1: DNA ISOLATION

• ISOLATION OF FOREIGN DNA – OR - FINDING THE GENE YOU WANT TO PUT INTO ANOTHER ORGANISM.

• STEP 2: RECOMBINANT DNA

• INSERTION OF THIS DNA INTO BACTERIAL PLASMID.

• STEP 3: TRANSFORMATION

• INSERTION OF RECOMBINANT PLASMID DNA INTO BACTERIA.

STEP 1: ISOLATION OF FOREIGN DNA

• INVOLVES FINDING THE GENE YOU WANT TO

ENGINEER INTO ANOTHER ORGANISM.

• THEN CUTTING IT OUT OF THE CHROMOSOME

(DNA) WITH RESTRICTION ENZYMES THAT PRODUCE

STICKY ENDS.

STICKY END OF ECOR1

4-21-2006 S. Stevens

• EcoRI

•G AATTC

•TTAAG

• HpaI

•AT

•NOT good for engineering.

• HindIII

•AAGCTT

• TCGAA

• PstI

•CTGCAG

ACGT

Step 2: Recombinant DNA

Formation

• Involves cutting the vector DNA (the

plasmid or other DNA used to deliver the

gene chosen) with the same restriction

enzyme.

• Allowing sticky ends to anneal.

• Bonding the pieces together with Ligase.

RECOMBINANT DNA

PLASMID RESTRICTION ENZYME EXAMPLE

ISOLATION OF FOREIGN DNA

RECOMBINANT DNA FORMATION

RECOMBINANT DNA

RECOMBINATION• INSERTION FOREIGN GENE INTO A HOST BACTERIAL CELL PLASMID.

• GOAL – TO PRODUCE MANY COPIES (CLONES) OF A PARTICULAR GENE.

• REPORTER GENE / MARKER GENE– TAGS GENE OF INTEREST – TO IDENTIFY THE PRESENCE OF A GENE.• OFTEN AN ANTIBIOTIC RESISTANCE GENE.

• IMPORTANT FOR IDENTIFYING TRANSFORMED CELLS

DISTINGUISHING TRANSFORMED FROM NON-

TRANSFORMED CELLS:

• INVOLVES

INCORPORATING AN

ANTIBIOTIC RESISTANCE

(REPORTER) GENE IN THE

PLASMID AND THEN

PLATING THE CELLS ON A

MEDIUM CONTAINING

THAT ANTIBIOTIC.

• ONLY THE TRANSFORMED

CELLS ARE RESISTANT, SO

ONLY THEY CAN GROW

ON THE MEDIUM.

STEP 3 TRANSFORMATION

•INSERT RECOMBINANT PLASMID

INTO BACTERIA.

•BACTERIA PRODUCED WITH THE

RECOMBINANT DNA EXPRESSES

THE GENE OF INTEREST.

VECTOR• THE WAY YOU GET THE

DNA INTO THE NEW CELL.

• EXAMPLES:

• PLASMIDS

• VIRUSES

• BALLISTIC GENE TRANSFER

(DNA COATED PARTICLES)

• EXOGENOUS DNA

CHARACTERISTICS OF A VECTOR1. CAN REPLICATE INDEPENDENTLY IN THE

HOST CELL – CONTAINS AN ORIGIN SITE.

2. HAS RESTRICTION SITES IN THE VECTOR.

3. HAS A REPORTER GENE THAT WILL ANNOUNCE ITS PRESENCE IN THE HOST CELL.

4. IS A SMALL SIZE IN COMPARISON TO THE HOST CHROMOSOME FOR EASE OF ISOLATION.

• BALLISTIC GENE

TRANSFER - THE USE OF

TINY DNA-COATED

PROJECTILES AS CARRIERS.

IT IS IMPORTANT TO

TRANSPORT DNA

THROUGH THE WALLS OF

INTENDED RECIPIENT

CELLS.

• PROJECTILES ARE

OFTEN KNOWN AS

MICRO PROJECTILES

• PLASMIDS WERE DISCOVERED IN THE LATE SIXTIES, AND IT WAS

QUICKLY REALIZED THAT THEY COULD BE USED TO AMPLIFY A

GENE OF INTEREST.

• A PLASMID CONTAINING RESISTANCE TO AN ANTIBIOTIC

CAN BE A VECTOR.

• THE GENE OF INTEREST IS INSERTED INTO THE VECTOR

PLASMID AND THIS IS THEN PUT INTO E. COLI THAT ARE

SENSITIVE TO AMPICILLIN.

• THE BACTERIA ARE THEN SPREAD OVER A PLATE THAT

CONTAINS AMPICILLIN.

• THE BACTERIA WILL NEED THE PLASMID TO SURVIVE AND IT

WILL CONTINUALLY REPLICATE IT, ALONG WITH YOUR GENE

OF INTEREST THAT HAS BEEN INSERTED INTO THE PLASMID.

4-21-2006 S. Stevens

• TRANSFORMATION - PROCESS OF

INTRODUCING FREE DNA INTO BACTERIA.

• COMPETENT CELL - A CELL THAT IS CAPABLE

OF TAKING UP DNA.

• ELECTROPORATION - THE USE OF AN

ELECTRIC SHOCK TO MOMENTARILY OPEN OR

DISRUPT CELL WALLS (WHICH ALLOWS DNA

TO ENTER THE CELL).

COMPETENT CELLS:

• SINCE DNA IS A VERY

HYDROPHILIC MOLECULE, IT

WON'T NORMALLY PASS

THROUGH A BACTERIAL

CELL'S MEMBRANE. IN

ORDER TO MAKE BACTERIA

TAKE IN THE PLASMID, THEY

MUST FIRST BE MADE

"COMPETENT" TO TAKE UP

DNA.

• THIS IS DONE BY CREATING SMALL

HOLES IN THE BACTERIAL CELLS BY:

• SUSPENDING THEM IN A

SOLUTION OF CALCIUM

CHLORIDE.

• THE CELLS ARE THEN INCUBATED

ON ICE.

• THEY ARE PLACED BRIEFLY IN A

HIGH TEMPERATURE (HEAT

SHOCK).

• THEN RETURNED TO ICE.

• THIS CAUSES THE BACTERIA TO

DEVELOP HOLES IN THEIR CELL

WALL TO TAKE IN THE DNA.

COMPETENCY

• THE PROCEDURE TO PREPARE COMPETENT CELLS CAN

SOMETIMES BE TRICKY. BACTERIA AREN'T VERY STABLE

WHEN THEY HAVE HOLES IN THEM, AND THEY DIE EASILY.

• A POORLY PERFORMED PROCEDURE CAN RESULT IN

CELLS THAT AREN'T VERY COMPETENT TO TAKE UP DNA.

• A WELL- PERFORMED PROCEDURE WILL RESULT IN VERY

COMPETENT CELLS.

• THIS IS TYPICALLY WHERE THE PROCESS FAILED IF CELLS

DO NOT TRANSFORM.

3 TYPES OF TRANSFORMATION:

GENE (OR DNA) CLONING

4-21-2006 S. Stevens

• DNA Cloning (many identical copies of specific DNA molecules) is NOT the same as…

• Organismal Cloning (identical genetic copies of specific individuals).

Traditional Cloning is NOT DNA Cloning

CLONING OF PLASMID

2 MAIN PURPOSES OF CLONING:

• 1. IT ALLOWS FOR A LARGE NUMBER OF

RECOMBINANT MOLECULES TO BE PRODUCED

FROM LIMITED STARTING MATERIALS.

• 2. PURIFICATION – LIMITING THE PRODUCTION

OF EXTRA DNA MOLECULES THAT DO NOT

CONTAIN THE TARGET GENE TO BE CLONED.

PGLO – GFPGREEN FLUORESCENT PROTEIN

FLUORESCENT• IN THE LABORATORY,

FLUORESCENCE IS EASILY ACHIEVED BY EXPOSING THE PROTEIN TO LONG RANGE UV LIGHT OR “ BLACK" LIGHT.

• THE FLUOROPHORE ABSORBS LIGHT IN THE UV-B REGION (395 NM.. PLUS A SMALLER ABSORBANCE PEAK AT 470 NM).

• IT EMITS LIGHT (FLUORESCES) AT 509 NM, WHICH IS IN THE GREEN PART OF THE VISIBLE SPECTRUM.

GFP AND LAND MINES• NEAL STEWART AT THE

UNIVERSITY OF NORTH CAROLINA IS DEVELOPING PLANTS THAT CAN DETECT LAND MINES.

• PLANTS COULD BE IDEAL BIOSENSORS FOR LAND MINES AS SEEDS WOULD BE SPREAD WIDELY AND EVENLY IN A SUSPECT FIELD.

• THE GENE THAT CAN ANNOUNCE THE PRESENCE OF LAND MINES IS GFP.

• THE GENE WILL BE EXPRESSED IN THE PRESENCE OF A LAND MINE.

GFP AND MICE

GLO FISH

• FLUORESCENT ZEBRA FISH WERE

SPECIALLY BRED TO HELP DETECT

ENVIRONMENTAL POLLUTANTS.

BY ADDING A NATURAL

FLUORESCENCE GENE TO THE

FISH, SCIENTISTS ARE ABLE TO

QUICKLY AND EASILY DETERMINE

WHEN WATERWAYS ARE

CONTAMINATED.