Modern Day Genetics
The Human Genome Project Two main goals: To determine the nucleotide sequence of all the DNA in human chromosomes To identify the location and sequence of every human gene A genome is the full DNA sequence of an organism
Some Interesting Findings Only about 1.5-2% of the human genome contains genes The remaining 98% includes repeated nucleotide sequences, regions that regulate genes and even DNA sequences inserted by viruses 3.2 billion base pairs Approximately 21000 genes
Genetic Technologies
Biotechnology The use of organisms to make useful products Micro organisms are used to produce: Vaccines Antibiotics Hormones food products enzymes that are added to detergents
Genetic Engineering The intentional production of new genes and alteration of genomes by the substitution or introduction of new genetic material Gives us the ability to modify the abilities of living organisms to meet specific needs in agriculture, industry and medicine
Genetic Recombination Combining genes from different sources – even different species – into a single DNA molecule
Applications
Genetically Modified Organisms GMO Any organism with genetic material that has been altered through genetic engineering A GMO is said to be transgenic if it has acquired one or more genes from a different type of organism Many applications in agriculture and medicine Unexpected effects
Genetically Modified Plants Characteristics of crops can be improved Delayed ripening improved nutritional content stress tolerance Resistance to spoilage or disease Transgenic varieties of tomato, potato, tobacco, soybean, walnut and apple
Pest Resistant Crops Incorporation of genes for a bacterial toxin Once toxin ingested by insect, its converted to a form that kills insect Allows for high yields of corn and other crops without having to spray chemical pesticides Some crops have traits with tolerance to herbicides or resistance to viral infection
Plants as Factories GM plants are used in biotechnology for development of pharmaceuticals Lines of safflower plants that produce authentic molecules of human insulin Can be used to treat the ever increasing number of diabetics Can reduce cost and increase yield Usually created from yeast or bacteria, but challenging to purify
Genetically Modified Animals Typically involved in vitro fertilization The process of fertilizing an egg in a test tube and transferring the embryo to the uterus Fertilize an egg with sperm from same species Desired gene then injected into fertilized egg Early embryo transferred to an animal’s uterus If embryo develops, result is GM animal with one or more genes from a third “parent” that may even be from a different species
Farm Animals and “Pharming” Goals of GM animals Better quality wool from sheep Pig with leaner meat Fish that will mature in a shorter time Make a transgenic animal that produces a large amount of rare biological substance Using animals to produce pharmaceuticals is called pharming Adding a gene for a desired human protein (eg. Hormone) to animal genome Gene is added in such a way that the desired human protein is secreted in the animal’s milk
Animal Cloning Dolly the sheep was first mammal to be successfully cloned from a somatic cell (1997) Goats, cows, mice, pigs, cats and rabbits have been successfully cloned
Regulating the Use of GMOs Concerns that transgenic species could be harmful to human health or to environment Escaped GM salmon competing with wild salmon Crops could pass new genes to closely related plants (herbicide resistance) – super weeds GM plant or animal products could have unknown risks to human consumers Human proteins produced in milk of transgenic mammal can differ slightly from natural human proteins Allergic reactions?
Genetic Technology in Medical Research Model organisms used to help determine gene function and to develop therapies Knockout mice Altering genome so that a gene no longer functions Can then study the line mice with new trait Obesity is an example
Gene Therapy Process of supplementing or replacing a gene in order to treat a medical condition Allows the body to make the protein that is not being made by the missing or malfunctioning gene Use of modified virus to deliver therapeutic gene Challenges Delivering gene to correct target Making sure the therapy works in long term
Well … What do you think!?
Questions Define the term “genetically modified organism”. Give two examples of genetically engineered micro-organisms. Identify each of the following as an example of biotechnology, genetic engineering or both. Using bacteria to make yogurt from milk Using goats to produce pharmaceuticals in their milk Using safflower plants to produce insulin Creating a transgenic rat for medical studies Why might someone with food allergies be concerned about eating a GM food?
5. Describe two challenges in gene therapy technology. 6 5. Describe two challenges in gene therapy technology. 6. Do you think someone should be allowed to undergo gene therapy for a disease such as cystic fibrosis, even if the treatment is experimental? Explain. 7. If you could clone a favourite pet, would you? Justify your response. 8. List 5 ways in which genetic engineering affects your life that you became aware of during this presentation.