Genetic Engineering

Entire organisms can be cloned  Clone  a genetically identical copy of a gene or of an organism  Cloning occurs in nature:  Bacteria (binary fission)  Plants (from roots)  Simple animals (regeneration or budding)

 Cloning occurs in mammals:  This occurs through a process called nuclear transfer  The nucleus is removed from an egg cell  Another nucleus (from the animal wishing to be cloned) is placed in the now “empty” egg cell

 There is potential controversy with cloning  Benefits:  Organs can be created for use in human transplants  There is a potential to save endangered species  Concerns:  There is a very low success rate  Clones are imperfect and less healthy than the original animal  Cloning decreases biodiversity

New genes can be added to an organism’s DNA  Genetic Engineering  changing of an organism’s DNA to give the organism new traits  Recombinant DNA  DNA that contains genes from more than one organism  Plasmid  closed loops of DNA that are separate from the bacterial chromosome and that replicate on their own within the cell

 Bacterial plasmids are often used to make recombinant DNA  Restriction enzymes cut plasmid and foreign DNA  A foreign gene is then inserted into the plasmid  The plasmid is put into a bacteria  The bacteria is turned into a tiny “gene factory” and is used to make many copies of the desired gene

Genetic engineering produces organisms with new traits  Transgenic  an organism that has one or more genes from another organism inserted into its genome  Transgenic bacteria:  The gene is inserted into a plasmid  The plasmid is inserted into bacteria  The bacteria expresses the desired gene

 Transgenic Plants:  Transgenic bacteria (with the desired trait) infect a plant  The plant expresses the desired gene  This can create large amounts of crops that have the desired gene  Genetically modified plants

 Transgenic Animals:  Used to study diseases and gene functions

Concerns about genetic engineering  There are possible long-term health effects from eating GM foods  There may be possible effects of GM plants on ecosystems and biodiversity