BIOTECHNOLOGY UNIT 5

GENETIC ENGINEERING Process where DNA is split into fragments and new DNA pieces are inserted The goal is to add one or more new traits that are not already found in that organism The new organism is now called a genetically modified organism or GMO Recombinant Genes – genes taken from one source and put into another in order to increase performance

JUST SOME OF THE LATEST ADVANCES IN THE WORLD OF BIOTECHNOLOGY Cloning DNA fingerprinting Genetically modified bacteria to synthesize products Genetically modified foods

CLONING Creating a genetically identical copy of something Cloning entire organisms becomes increasingly more difficult the more complex the organism is (ex. Humans are harder to clone than worms) and so it is very recent and for some species has not been perfected yet

HOW CLONING WORKS DNA is extracted from an adult cell An egg for this same species has it’s DNA removed The empty egg is filled with the adult DNA The egg is implanted into a surrogate mother The baby born from this egg is genetically identical to the adult from which it was cloned It will not be the same age as the animal it was cloned from (it’ll be a baby)

WHY CLONE? To create identical cells for research purposes To maintain a genetically desirable species of plant or animal To create a missing organ or tissue for treatment of human diseases To save endangered or extinct species

STEM CELLS

DNA FINGERPRINTING Identifying the pattern of certain sequences in parts of a person’s DNA to determine if two samples come from the same person, related persons, or two non-related individuals Everyone has a unique sequence of DNA (even identical twins) In order to be an effective tool, we need to get DNA from many people to determine how often certain patterns show up in the population

HOW DNA FINGERPRINTING WORKS The DNA is isolated from a cell sample and many copies are made with a process called PCR The DNA is cut into pieces using restriction enzymes (they cut only at specific sequences) The DNA is run on a gel electrophoresis to separate the pieces (separated based on size) Comparisons of these pieces of DNA are made to determine identity or relationships

WHAT DOES A DNA FINGERPRINT LOOK LIKE?

WHAT CAN DNA FINGERPRINTS BE USED FOR? Paternity/maternity tests To determine if a suspect was at a crime scene To identify a murder victim To identify a soldier killed in the line of duty To determine identity

GENETICALLY-MODIFIED BACTERIA Inserting new genes into a bacteria to trick it into making a product for us Although each bacteria usually doesn’t make much product, millions of bacteria can be grown in bioreactors at the same time, and the product harvested from all of them at once

HOW ARE GENETICALLY-MODIFIED BACTERIA CREATED? A piece of DNA containing the gene for the desired product is cut out A plasmid (circular bacterial DNA) is cut out as well The piece of DNA and the plasmid are fused together The plasmid is transformed into the bacteria The plasmid either stays in whole or the gene crosses over into the bacteria’s DNA

SOME PRODUCTS NOW SYNTHESIZED BY BACTERIA Biodiesel fuel Chemicals to block an HIV infection Photographs Human insulin for diabetics Plastics

GENETICALLY-MODIFIED FOODS Livestock or produce that has received new genes to make the product healthier, resistant to pest or more nutritious The process is similar to that used to create genetically-modified bacteria, but the genes are being inserted into multi-celled organism instead

HOW GMO ARE MADE The process varies slightly between each species, particularly between plants and animals, however some aspects are the same Changes are made to the organism’s DNA by inserting a useful gene into the egg cell This changed egg is then implanted into a mother and the baby born hopefully has the desired trait

SOME GENETICALLY MODIFIED ORGANISMS (GMO)

WHY MAKE GMOS? To give plants resistance to certain pests without the use of pesticides To make plants drought resistant To make cows that produce more milk To make vegetables that can undergo long transport without over-ripening To make chickens that contain extra vitamins that may be missing from our diets

THE ETHICS OF BIOTECHNOLOGY Despite all the exciting things that biotechnology can do or will do in the near future, there are things to consider: Would it be ethical to clone a human? Why or why not? Should your insurance company be allowed to have access to your DNA profile if it detected some disease? How can the bacteria in bioreactors be disposed of once they are no longer useful? What happens to the natural balance when GMO are sent out to compete with natural plants in the environment?

10/28 WARM-UP 1.How do we separate DNA? 2.What is a clone? A natural example? 3.What is a GMO?