BIOTECHNOLOGY & GENETIC ENGINEERING AN INTRODUCTION Professor Chrissie Rey School of Molecular and Cell Biology.

BIOTECHNOLOGY &GENETIC ENGINEERING

AN INTRODUCTION

Professor Chrissie ReySchool of Molecular and Cell Biology

• Biotechnology can be regarded as:– Innovation in the use of any biological substance to

make products of use to humans. • This began in prehistory e.g breadmaking

– In a more specific sense, biotechnology refers to the application or modification of genetically modified (GM) organisms for improvement or enhancement in agriculture, health or industry.

– Genetic Engineering is a means of altering a biological organism

– Genetic Engineering of plants for e.g. is inserting a gene (showing a particular trait e.g. fruit size) from one source, into a plant. The source can be from another plant, animal or human.

What is Biotechnology?

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

WHAT IS GENETIC ENGINEERING?

• GE is the genetic manipulation of organisms such as animals, plants or bacteria

• This is usually achieved through cloning (plants and bacteria) or in the case of animals through nucleus transfer from donor cell (parent you wish to clone) to recipient cell (egg cell from another parent whose nucleus has been discarded)

WHAT IS CLONING?

DOLLY THE SHEEP: FIRST GENETICALLY ENGINEERED OR CLONED ANIMAL

• Red biotechnologies refer to medical or pharmaceutical processes e.g. designing an organism to produce antibodies

- Engineering of genetic cures such as gene therapy- Disease diagnosis tools- Insulin for diabetes- Vaccines for HIV

• Green biotechnology is agricultural crop processes• White biotechnology is industrial biotechnology e.g.

design an organism to clean up pollution or produce a chemical

- e.g. production of chymosin from GM yeast for cheese making

• Bio-economy refers to investments and economic output of all biotechnologies

Applications of Biotechnology

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

BIOTECHNOLOGY FOR AFRICA

DISEASES AND PARASITES• Malaria (mosquito control)• HIV• Hepatitis A (food borne diseases)• TB

FOOD SECURITY• Yield• Quality (nutritional value)• Pest and disease resistance• Drought resistance

BIOTECHNOLOGY FOR GAUTENG

INDUSTRIAL BIOTECHNOLOGY

PLANT GENETIC ENGINEERING

• Humans have intervened in the reproduction and genetic makeup of plants for thousands of years.– Neolithic (late Stone Age) humans domesticated

virtually all of our crop species over a relatively short period about 10,000 years ago.• However, even for these plants, genetic modifications

began long before humans started altering crops by artificial selection.

• For example, the wheat groups that we harvest are the result of natural hybridizations between different species of grasses.

Neolithic humans created new plant varieties by artificial selection

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

• Whatever the social and demographic causes of human starvation around the world, increasing food production seems like a humane objective.– Because land and water are the most limiting

resources for food production, the best option will be to increase yields on available lands.

– Based on conservative estimates of population growth, the world’s farmers will have to produce 40% more grain per hectare to feed the human population in 2020.

Biotechnology and the food crisis

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Gene of interest Gene of interest integrated integrated into into AgrobacteriumAgrobacterium

Plant tissue transformed Plant tissue transformed

Transformed cells culturedTransformed cells cultured

Plantlets grown upPlantlets grown up

Plants tested for successful Plants tested for successful transformation (i.e. foreign transformation (i.e. foreign gene inserted)gene inserted)

Phenotypes recorded.Phenotypes recorded.

Genetic analysis to Genetic analysis to determine copy number.determine copy number.

Crop is tested for “inserted Crop is tested for “inserted trait”trait”

Comparison of GE crop with Comparison of GE crop with non-GM cropnon-GM crop

SA plant biotechnology focus

• Primarily aimed at controlling diseases and pests.– Insect pests.– Virus pests.– Fungal and bacterial diseases.

• Improving the storage properties of food.• Improving weed control.• Improving yield and quality of foods.• Protecting natural resources.• Drought and salt tolerance.

South African GM crop acreage 2003

Crop Hectares Percentage of total crop

White maize 58, 000 2.8%

Yellow maize 176, 000 20%

Soya 12, 000 11%

Cotton 24, 000 80%

•0.5million hectares of biotech crops grown in SA (2005):

8th in the world (world total 90 million hectares).•Update 2006: Combined trait bollworm and herbicide (stacked)

• cotton variety now released in SA

WHO BENEFITS?

The Farmers!!!!

Average gain using Bt-cotton is 349kg/hectare@R3/ha is R1047

profit per ha

Transgenic maize growing in South Africa

Benefits of Bt maize (2)

• Fumonisins produced by Fusarium linked to oesophageal cancer

• Eastern Cape region in SA has one of the highest incidences of oesophageal cancer in the world

• Associated with home grown maize (testing for mycotoxin levels not practical)

Benefits of Bt Maize

• Bt maize controlled stalk borers with 97% efficiency, against 75-85% efficiency from chemical insecticides.

• Bt maize gave yield advantages on average of 10% in South Africa

• Reduction in insect attack reduces fungal infection

• Many people, including some scientists, are concerned about the unknown risks associated with the release of GM organisms into the environment.– Much of the animosity regarding GM organisms is

political, economic, or ethical in nature, but there are also biological concerns about GM crops.

– The most fundamental debate centers on the extent to which GM organisms are an unknown risk that could potentially cause harm to human health or to the environment.

Plant biotechnology has incited much public debate

Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

CAN WE CLONE A HUMAN BEING?

GM FOOD – FEAR HAS BIG EYES

CONCERNS(Be willing to address concerns)

• Farmers– Access– Sustainability– Benefit sharing

• Human Health– Multi-drug resistance– Allegenicity

• Environment– Weeds– Biodiversity

What to tell the consumer?

• General information on GM food should be provided in a reasonable and balanced manner

• South Africa has a government-funded programme on public understanding of biotechnology to set the information in context

What does the public think?Buying response to GM food

0

5

10

15

20

25

30

35

40

Never buy Not buy until more info Buy but get more info Buy Depends

Gauteng

Cape Town

Not buy till more info

Buy but get more info

Buy DependsNever buy

Perc

enta

ge

Food Labeling

Labeling should address issues of:• Safety• Nutrition• Ethics (religion)

Procedures for decision making under the GMO Act

PostMarket

Transfor- mation

LineSelection

VarietyDevelopment

FieldProduction

MarketGeneDiscovery

GH & FieldEvaluation

ProductConcept

Ag Biotechnology Product Path Safety Assessment - Phase I

Safety / Registrability Assessment

Choice of Genes / Proteins– trait of interest– selectable marker

Source of Genes– safety (history of safe use)– ethics

Environmental / Ecological Concern– gene– specific crop

Early Allergology and Toxicology Assessment

GO / NO GO decision

Discovery Line Selection Product Advancement

Environmental Assessment

Conclusions• GM Food is not inherently unsafe• Most applications facing Africa in the near term will

be for crops such as Bt maize that have already received regulatory approval elsewhere in the world

• Data generated elsewhere are in many cases still applicable – no need to produce a whole new data file

• Regulators should take care to assess safety issues objectively, not be swayed by public pressure

• Take care to focus on what you need to know, limit the “nice to know” questions

• Safety issues should not be confused with issues of ethics or personal choice