Module 6: Genetic Change PDF

Module 6: Genetic Change Mutation - How does mutation introduce new alleles into a population? Allele: different forms in which one gene can be expressed Mutations: permanent change to the DNA sequence of an organism. They can occur anywhere in a person's DNA sequence; pro...

Module 6: Genetic Change Mutation - How does mutation introduce new alleles into a population? Allele: different forms in which one gene can be expressed Mutations: permanent change to the DNA sequence of an organism. They can occur anywhere in a person's DNA sequence; protein coding gene, RNA gene, non-coding DNA. Why are mutations important? - Mutations create variations in phenotype and these variations can be inherited. This variation increases the chance of a population's survival during environmental change. (the only way to introduce new alleles into a population) - Without mutations, natural selection cannot occur. Variations that help an organism survive & reproduce are passed to the next generation Error in DNA (mutation) ↓ Error in transcription ↓ Error in translation ↓ Error in sequence of polypeptide chain ↓ Function of protein does not work properly ↓ Change in phenotype expression The Criteria for Mutations: 1. The origin of the mutation: spontaneous or induced mutation (mutagen) 2. The amount of genetic material changed: point mutation or chromosomal mutation 3. The effect of the mutation on DNA: - Point mutations: substitution, insertion, deletion (frameshift) - Chromosomal mutations: deletions, insertions, translocations, duplications 4. The effect of the mutation on phenotype: silent, missense, nonsense 5. Heritability of mutation: somatic or germline  explain how a range of mutagens operate, including but not limited to: Mutagens Spontaneous Mutations - Agents that lead to mutations - Happens spontaneously / unpredictable - Mutations can occur due to exposure - Can occur when mistakes are made during to mutagens DNA replication or transcription - Not frequent & occur naturally during a person's lifetime – electromagnetic radiation sources Ionising Radiation - X Rays, Gamma Rays Radiation can break chemical bonds causing damage to DNA. Multiple fractures in the DNA can overwhelm enzymes causing mistakes to be made and mutations to occur. UV Rays Ultraviolet radiation from the sun can promote a chemical reaction in the DNA, causing certain bases next to each other to fuse together e.g. two thymine bases. These thymine dimers cause a bulge in the DNA and can change or disrupt DNA expression, preventing normal transcription and replication – chemicals Intercalating agents Some chemicals insert themselves between bases of a DNA sequence. This insertion causes the the DNA structure to stretch, “fooling” DNA polymerase into inserting an extra base opposite the intercalating molecule causing frameshift Base analogous These chemicals are similar in physical structure to nitrogenous bases. During replication these molecules may be incorporated instead of nitrogenous bases and hence a mutation Reacting Chemicals These chemical mutagens react with the nitrogenous bases and chemically modify the DNA causing mutation. Example: Carcinogen is a chemical found in cigarettes that causes damage to lung cells. – naturally occurring mutagens Biological Mutagens Metabolism processes result in the release of naturally occurring chemicals such as free radicals. Free radicals cause oxidation of DNA, breaking DNA strands, which interferes with DNA replication and transcription. Viruses Viruses insert their genetic information into the chromosomes of the host cell, causing disruption to normal cell function e.g. HPV is an oncogenic (cancer causing) virus that causes cervical cancers.  compare the causes, processes and effects of different types of mutation, including but not limited to: – point mutation: mutation changing one or very few nucleotide bases in a gene sequence e.g. sickle cell anemia Base Substitution: one base is substituted for another. insertion or deletion: when an extra base is added or deleted -> only leads to frameshift Effect on proteins Nonsense: changing an amino acid to a stop codon, cutting the protein short. This resulting protein is normally non-functional Missense: a point mutation that results in 1 amino acid change. E.g. sickle cell anaemia occurs when the triplet CTC changes to CAC causing glutamate to be swapped with valine, altering the shape of haemoglobin and causing sickle cell shaped blood cells. Silent: a change in the DNA sequence that does not cause a change in amino acids. This is due to the swapped base in the triplet, still coding for the same amino acid as the old one. Frameshift mutation: an insertion or deletion shifts the entire reading frame of RNA, leading to the creation of a whole sequence of incorrect amino acids and production of a non-functional protein. Since the transcription of DNA is read in codons of three bases, a deletion or insertion of three bases will only affect one amino acid. – chromosomal mutation: large scale mutations that affect the overall structure of a chromosome or the entire number of chromosomes in a cell are altered. Changes to the Structure  Deletion: a section of DNA is removed and not replaced, causing a reduction in the number of genes in a chromosome. Insertion/Duplication: a portion of DNA is duplicated then inserted, increasing the number of genes on a chromosome. Inversion: a section of DNA is removed, turned 180 and then reinserted into the chromosome so that the bases are in reverse order. Translocation: a section of DNA is moved from one chromosome to another. Changes to Chromosome number (Aneuploidy) - Caused by nondisjunction during meiosis or mitosis - Nondisjunction is the failure of homologous chromosomes to separate during cell division (Meiosis1 - homologous chromosomes separate, Meiosis 2 - chromatids separate) - Outcome are cells with extra or missing chromosomes Trisomy: an extra copy of a chromosome present. Can lead to shortened life span or development problems. Example Trisomy 21 means there are three copies of chromosome 21, resulting in down syndrome.  distinguish between somatic mutations and germ-line mutations and their effect on an organism Somatic Mutation Germline Mutation - Mutation in a body cell - Mutation in a sex/gamete cell - Not heritable (can be passed onto offspring) - Occurs throughout a person's - Heritable lifetime - Can be inherited from birth - Present only at site of mutation - Mutation will occur in all cells of - Mutated cell can divide, the offspring’s body as original growing tissue with this error cell was already mutated (cancer) assess the significance of ‘coding’ and ‘non-coding’ DNA segments in the process of mutation The DNA sequences which encode for proteins are known as coding DNA. The sequences which do not encode for proteins are known as noncoding DNA. Segment Function Significance of a mutation? Coding Exons Codes for proteins that carry out biological Can directly impact the sequence of amino (gene) functions. acids and therefore affect the functioning of proteins. Changed DNA code = changed mRNA = mutated protein Non-coding Enhancer/ Enhancers turn on or enhance the expression Can cause too much or too little production Silencers/ of a gene. of proteins or the wrong protein to be regulators Silencers turn off or slow the expression of a produced if turned on. gene. E.g. diabetics Promoters Tell the enzyme RNA polymerase where to Mutation can result in polypeptide chains bind RNA to DNA which begins the not being fully transcribed, causing transcription. deficient proteins Introns Code for their own removal during mRNA Have the potential to affect splicing of DNA (gene) splicing (end of transcription) (mutation in introns causes removal of exons = deletion). investigate the causes of genetic variation relating to the processes of fertilisation, meiosis and mutation Genetic Variation occurs due to: Mutations: only source of new alleles within a population (germline mutations). Sexual Reproduction: responsible for the combination of alleles. - Random Fertilisation: Recombination of haploid cells during fertilisation is random, introducing different allele combinations - Meiosis: Law of segregation: homologous chromosomes (anaphase 1) and sister chromatids (anaphase 2) must separate  Independent assortment: chromosomes separate into daughter cells independently of one another (as in not all father chromosomes go to one cell and not all mother chromosomes go to the other cell) Crossing over: new combinations of alleles so each gamete is unique Genetic variation can be beneficial for the survival of the population as it gives some individuals an advantage over the rest of the population. Genetic variations can also be negative and lead to diseases or they can have no effect. Genetic variations are not as beneficial to a particular individual but are more helpful to the survival of the population if there are unexpected changes in their environment. evaluate the effect of mutation, gene flow and genetic drift on the gene pool of populations Mechanisms for changes in frequency of a gene pool: Mechanism Definition Example Effect on Gene Pool Natural Selective pressures such as predators and mating result in certain characteristics increasing an individual's chance of survival. Therefore Selection unfavourable traits are not passed to the next generation, reducing frequency of this allele in the gene pool Mutations Direct change in the DNA of an individual, introducing a Introduction of new green frogs that are better Increases new allele into a population. The only way new alleles suited to the environment, resulting in greater number of can be created within a population. frequency of green frogs in the gene pool over alleles in a time. population Genetic Drift A random change in the environment causing random Founder Effect: a small group of individuals are Decreases (chance) alleles in the population to be reduced in frequency. separated from the main population and become number of Different to natural selection as it is not linked to adaptive the founding members of a new population. This alleles in a advantage to environmental change as it is CHANCE of new population has different allele frequencies to population who survives. the original population. (Armish have 6 fingers) Small populations are greatly affected by genetic drift. Bottleneck Effect: lots of a population died due to random environmental change and by chance certain individuals survived (within this decreased population there is decreased genetic variation) Gene Flow Movement of genes between populations. (each A blonde-haired, blue-eyed family from Sweden Increase and (migration) population introduces more alleles into the other moves to India where the children grow up, decrease the population), increasing alleles present in gene pools. marry Indians and produce offspring who now number of (migration) have the blonde-haired, blue-eyed alleles alleles in a Alleles may be lost due to emigration (individuals that population. migrate take a specific allele out of the frequency) Gene flow can also result in introduction of a harmful mutation to a new population (disease). Lack of gene flow results in speciation. Evolution: changes in characteristics of a species overtime - When the gene pool of a population changes, evolution occurs.  Biotechnology - How do genetic techniques affect Earth’s biodiversity? Biodiversity Total variety Genetic and variability Ecosystem Diversity Species& between Diversity Total Diversity within all Total variety variety of Total of classes of genes varietyasand species well ecosystems (allele types as theof and the frequency) What is biotechnology used species ecosystems for? in biotic within a livingthey which on components species Healing the World Earth reside interacting Feeding the World within an - Reducing rates of infectious disease and serious ecosystem - improves crop insect resistance, enhances crop illnesses, saving millions of lives herbicide tolerance and facilitates the use of more - Tailoring treatments to individuals to minimize environmentally sustainable farming practices health risks and side effects - Lowering use of agric. Chemicals in farming - Creating more precise tools for disease detection - Higher crop yield with fewer inputs - Developing crops with enhanced nutrition investigate the uses and applications of biotechnology (past, present and future), including: – analysing the social implications and ethical uses of biotechnology (not changes to embryo material), including plant and animal examples & evaluating the potential benefits for society of research using genetic technologies (changing the DNA - only GMO, CRISPR, and cloning) - evaluating the changes to the Earth’s biodiversity due to genetic techniques Biotechnology: any commercial exploitation of biological processes. Can be groups in 4 categories: medicine, industry, environment, agriculture. Genetic Technology Social implications Ethical implications Selective Breeding, artificial - Increase in yield production - Exaggerated features can negatively affect pollination & hybridisation (pesticides, size, resistance, faster growth) = less land needed the health of an animal To get desired combination of E.g. Corn selectively bred to have a bigger kernel. - Is increase in global food and increased favourable characteristics Mules were bred from a horse and a donkey. Mules therefore nutritional value being used to support aided in transport as they were strong and had endurance developing countries or making an obese past E.g. Labrador and Poodle - characteristic for a family friendly dog population more obese? that is hypoallergenic - Pest resistance can reduce pesticide runoff that can harm surrounding environment - Increase in health benefits of food - Higher profits - Faster process of reproduction so endangered species can be encouraged - Less environmental damage because of more efficient food production - Susceptibility to extinction - Inbreeding leads to diseases - Reduces biodiversity (consistent selection of the same traits) Fermentation - use of natural microorganisms → a natural process - people argue that microorganisms are Cheese, wine, beer, bread used to make to food for survival unnatural for people to consume production. Bread was - Improve nutrition/yield of crops → reduces mass fermented by the biological starvation and poverty organism yeast present in the air. Enzymes are added to milk - natural milk (without sterilization technology) is to speed up the curdling dangerous and illegal to sell (in the US) → process. sterilization is unnatural. Many have argued that raw milk is safer & healthier than pasteurized milk past cultures. - humans need microbial life to survive, so fermentation gives necessary nutrients - opens new jobs Vaccines - Less burden on health care systems as people are healthier - Developing countries who often need these Contain weak/inactive antigens through use of plants for medical treatment (mould was vaccines or medicine most cannot afford that trigger the immune system found to treat infections - penicillin has antibacterial - Vaccines and antibiotics are often tested to resist it in the future. Newer properties) on animals which can harm their health or vaccines contain blueprints for - Prevent disease before outbreak occurs cause pain and distress antigens rather than the antigen - Can eradicate diseases (e.g. smallpox) - Deliberately breeding animals for research itself so the immune system - Longer life spans such as promoting tumor growth can harm knows how to fight it in the - Evolution of resistant strains of pathogens resulting from animals future. inappropriate use of antibiotic has resulted in new strains of Medicine & Antibiotics viruses Many medicinal plants are used - Changing the genomes of other organisms and introducing to make medicine. The chemical them to an ecosystem can lead to invasive behaviour and penicillin was found to be reduction in biodiversity produced by a fungus that stops - Identification of a plant than can be used for pharmaceutical bacteria from growing. purposes would raise the value of the material, resulting in present exploitation and species loss Artificial Insemination - Transport of sperm to other communities to increase genetic - Who has access to these genetic Taking the sperm from a male variation resources, can cause unfair sharing of with desired traits and artificially - Animal conservation to maintain biodiversity by encouraging benefits inserting it into several females reproduction (Southern white rhino was brought back from - Could be stated as an unnatural process the brink of extinction) - Artificial insemination can appear to violate present - Desired traits are passed onto offspring, increasing output / animal rights, because they involve resources (meat, milk) impregnating animals for human ends as if - decreases genetic variation as certain traits are continuously the animals were nothing more than selected, artificially increasing the allele frequency of these human property, rather than treating the traits animals as being of value in themselves - susceptibility to extinction due to decreased variation - inbreeding leads to diseases - genetically modified crop varieties severely reduces the number of non-GMO varieties causing loss of traditional varieties & decrease in biodiversity - Possibility for GMOs to have unknown negative health side effects due to differences in nutritional content, allergic response, or undesired side effects such as toxicity, organ damage, or gene transfer Transgenic species (GMO) - Can manipulate food to provide greater nutritional value - Who has access to these genetic One or more DNA sequences (addressing hunger in poor and developing countries - resources, can cause unfair sharing of from another species is Golden Rice has high Vit. A content) benefits introduced by artificial means. - Increased yield, disease and pest resistance, weather - Can cause an organism to have harmful Animals usually are made resistance and enhanced flavor (you don’t have to spray characteristics (e.g. Modern pigs have transgenic by having a small plants with chemicals = less damage to environment = been bred to grow extra fast - some breeds sequence of foreign DNA healthier population) now grow too fast for their hearts, causing injected into a fertilized egg or - Potential to have pharmaceutical uses (Tracy the sheep was discomfort when animals are too active) developing embryo. the first transgenic mammal created - produced the human - Genetic engineering and selective protein alpha1-antitrypsin in her milk (was a potential breeding appear to violate animal rights, present pharmaceutical for the treatments of cystic fibrosis and because they involve manipulating animals emphysema) for human ends as if the animals were - Transgenic organisms will become dominant as they were nothing more than human property, rather modified to increase survival, therefore causing extinction of than treating the animals as being of value natural organisms (genetic erosion) in themselves - Transgenic organisms introduced to an ecosystem can lead - Vegetarians or religious people may be to invasive behaviour and loss of biodiversity (changes concerned animal genes are used in plant biodiversity of natural environment) products - We don’t know the long term effects of eating GMO foods - Is adding human genes to animal genomes (new allergens may be created e.g. GMO soybeans were immoral using genes from brazil nut - people with allergies to brazil - Negative environmental impact nut are allergic to soybeans) - Farmers in the developing work cannot compete in markets  as they do not have access to GMO technology (social inequality) DNA sequencing - Provide guidance on future treatment options - Can have negative psychological impacts Technology can sequence the - Increase awareness of susceptibility to a hereditary disease - on a patient who carries a harmful mutation entire DNA base sequence of allowing for preventative measures to be taken and early such as a BRCA gene your chromosomes to identify detection - Certain individuals do not want to know variants that may be disease - Allows us to identify embryos with genetic diseases (BRCA1 their risk to the disease causing. or BRCA2 carriers) - Can cause descrimination in health present - Can be very expensive insurance - Privacy of health organisations having your DNA sequence - Ethical issue of where DNA sequencing stops as screening embryos could lead to selective breeding (designer babies) – researching future directions of the use of biotechnology Cloning - Can increase genetically ‘perfect’ animals or crops that - Cloning goes against certain religions Researchers remove a mature provide the greatest produce (output, nutrition, quality, - Uncertain/unpredictable results: over 89% somatic cell, such as a skin cell, growth rate) of animals and human cloning attempts from an animal that they wish to - Cloning helps with regenerative medicine and stem cell have recorded a fail, which means that copy. They then transfer the treatment for burn victims, reconstructive surgeries etc. animal DNA is only exposed to risk in the DNA of the donor animal's - Can help with plants or animals who cannot reproduce whole process somatic cell into an egg cell that - Can be used as a source for organ replication for organ - Only the rich can afford has had its own DNA / nucleus transplants - Human clones become a commodity to be removed. - Decreases genetic diversity bought and sold future - Cloning an organism does not provide an exact replication as environmental factors affect phenotype expression - If animal A has the a disease/fault, all clones will have this fault Gene editing / Splicing - Gene editing could completely treat diseases promptly and - The choice of being able to edit and design Cutting out genes using not just the symptoms, reducing and eliminating future health babies is a controversial topic restriction enzymes (Cas9) that consequences (by removing harmful DNA mutations) - Can possibly cause future inequality in cut DNA at a specific base. - Some gene editing tools are inexpensive compared to society. Gene-editing can create ‘designer CRISPR-Cas9 current therapies, benefiting individuals and the economy babies’ with enhanced physical features, Cas9 enzyme contains a guide (CRISPR). intelligence, or athleticism that may create DNA which is complementary to - Gene editing is a recent technology that isn’t fully superiority in society. the targeted gene. The Cas9 researched, there are potential side effects such as cancer - May be against religious beliefs DNA cutting enzyme is - Can reduce biodiversity (GM mosquitoes) - Can cause racial descrimination introduced to a cell and locates - A gene drive can help improve “organism.” the DNA strand and cuts it. Then a replacement healthy DNA strand is replaced. future Answering question: if a question asks for genetic technology you can’t use all biotechnology - Define biotechnology - Give examples of a few biotechs - What are multiple examples of benefits of these two biotechnologies  Genetic Technologies - Does artificial manipulation of DNA have the potential to change populations forever? Genetic Technology: a range of activities concerned with understanding gene expression, taking advantage of natural genetic variation, modifying genes and transferring genes to new hosts. Gene technology is a modern branch of biotechnology that allows direct manipulation of DNA or removal of a gene, or the transfer of a gene from one species to another. E.g. transgenic organisms investigate the uses and advantages of current genetic technologies that induce genetic change Uses & Advantages Reproductive Artificial - Improves conservation efforts of endangered species technologies Insemination - Allows couples experiencing infertility to fall pregnant (in uterus) - Can produce stronger more efficient produce through selecting desired traits to pass onto the next generation - Allows control over the time of breeding - Allows the storage of sperm and insemination into multiple individuals In Vitro - A process through which an egg is removed from the ovaries and fertilised by injecting a single Fertilisation sperm into the egg then transferred into the uterus (in lab) - Higher fertility rates than artificial insemination - Can be used for conservation of animal species - Can help mothers struggling with contraception to enable pregnancy - IVF allows farmers to choose the healthiest animals to reproduce allowing for greater output and quality e.g cattle are bred for a high quality meat Artificial - Plants with the ideal characteristics such as size and seed number can be used for Pollination reproduction to increase yield, also meaning less strain on the environment - Scientist have created medicine from plants - Higher yield = higher profit for farmers = helping developing countries Cloning Gene Cloning - Larger and more resilient food can be grown techniques - Genes can be copied to allow for DNA sequencing - Transgenic E-coli can produce insulin for people with diabetes - Create copies of DNA or segments of DNA to be inserted into animal embryos to produce transgenic organisms - Can be used to grow replacement organs - Genes can be used to inserted into bacteria to create transgenic bacteria (adenovirus in gene therapy - virus delivers gene to affected tissue) Whole-organism - Can replicate animals or plants with ideal characteristics to maintain high output levels cloning - Increase population numbers fast - Create security in the global food supply Recombinant Gene Sequencing - A laboratory technique used to find the exact sequence of nucleotide bases in the sequence of DNA a patient's DNA technology - Used to identify location and function of a gene that can be used in transgenic organisms (use these in - Used to identify DNA variants / mutations in the gene sequence that may suggest the cause of exams) a disease e.g. if a person carries a BRCA1 or BRCA2 gene that increases the risk of breast cancer occurring - Knowledge of a mutation can guide doctors on treatment options and preventative measures for a disease such as gene therapy - Scientists can use sequence information to determine which stretches of DNA contain genes and which stretches carry regulatory instructions, turning genes on or off - Can suggest family members may also carry a genetic disease increasing awareness - A study has found the entire sequence of a healthy human and therefore it is easy to identify a mutation - New methods of gene sequence can now target specific chromosomes, therefore decreasing costs of procedure and time - Can be used in combination with pre-implantation screening to reduce diseases within a  population Transgenesis - Enables the transfer of a gene from one species to another - Could lead to larger yields, capable of crops growing under stressful environments, resistance to disease and pests, enhanced nutrition composition, faster growing and improved quality of e.g. silk - Can decrease spread of specific diseases amongst animals - Can create disease restraint medication Gene Therapy - Can be used to repair / replace faulty genes in an attempt to cure a disease or improve the Normally involves bodies ability to fight diseases taking a desired gene - Can be done at embryonic stage to prevent the development of a hereditary disease and inserting it into - Can regulate gene expression modified viruses that - No donor or other organisms DNA is needed cannot cause a disease. This virus - holds promise for treating a wide range of diseases, such as cancer, cystic fibrosis, heart then delivers genetic disease, diabetes, hemophilia and AIDS material into a cell’s nucleus causing the cell to express this gene. CRISPR - Has the ability to edit a DNA sequence by cutting out or putting in nucleotide bases CRISPER is one - Can correct genetic defects -> treating and preventing a disease -> laboratory method of - Can develop new plant varieties that are indistinguishable from those developed through altering the DNA and traditional breeding methods can be used as a tool - GM mosquitoes - Researchers have used CRISPR/Cas9 gene editing to target a specific for gene therapy. It involves the cutting and gene tied to fertility in male mosquitoes. GM male mosquitoes carry a gene that causes removal of a gene offspring to prematurely die. They are released in large numbers to overwhelm existing male populations. This suppresses population growing as females mate with GM males, reducing reservoir size - Can reduce biodiversity as it is a food source in the food chain Genetically - Virus RNA that codes for antigen producing genes are injected into the DNA of human cells. These Engineered cells synthesis virus antigens that stimulate the immune system response Vaccines - Alternatively RNA that codes for antigens is inserted into the plasmid of bacteria. Recombinant RNA vaccines are bacteria multiply and produce virus antigens. Virus antigens are extracted and used in the vaccine. created by inserting viral RNA into cells. This viral RNA codes for surface protein antigens. This stimulates the immune system response against the virus. compare the processes and outcomes of reproductive technologies, including but not limited to: - artificial insemination Male gametes are collected and inserted into the uterus of a female. - Artificial pollination Pollen is collected from the male part of a flower (stamen) and transferred to the female part of a flower (stigma). Process Outcome Similarity Differences Similarity Differences Both involve - artificial Insemination involves the allow to produce artificial pollination collection of male transfer of sperm one female at a time offspring with desired involves production gametes which are - Sperm can be frozen and transported characteristics but of flowers plants then transferred over longer periods of time both lead to a while artificial into/onto the - artificial pollination requires the collection reduction in genetic insemination is used female. of pollen by milling flows which are then diversity. to produce animals blown or sprayed onto multiple plants at a time - Also if you want to stop self pollination anthers have to be cut off and bags need to be placed over the flower to stop further cross pollination investigate and assess the effectiveness of cloning, including but not limited to: - Whole Organism Cloning Somatic cell nuclear transfer 1. A somatic cell has its nucleus removed from sheep 1 2. A mature egg is removed from sheep 2 and its nucleus is taken out 3. Nucleus from sheep 1 is inserted into egg from sheep 2 4. Electricity stimulates division of zygote to form an embryo 5. Embryo is implanted into a surrogate mother and will create an identical offspring to sheep 1 Artificial twinning 1. Early embryo (cluster of identical cells) is collected 2. Cells are separated and continue to divide forming separate embryos 3. Each embryo is implanted into a seperate surrogate mother Effectiveness: more effective than selective breeding in producing organisms with desired features but it can be more expensive - gene cloning Inserting a Gene into a bacteria 1. Cut out desired gene using restriction enzymes 2. Cut the bacterial plasmid with the same restriction enzymes 3. Use DNA ligase to paste gene into the plasmid 4. Using heat shock, Insert the plasmid into bacteria 5. When bacteria goes through binary fission, they make copies of the gene E.g. cloned bacteria produce insulin which is harvested for patients with diabetes PCR (Polymerase chain reaction) 1. A sequence of DNA sample is extracted 2. Denature DNA - Heat separates the double stranded DNA into single strands  3. Add free nucleotides, primer and polymerase 4. Polymerase adds free nucleotides to exposed DNA strands (starting at the primers) to make a copy of the DNA 5. This process is repeated making many copies of DNA Effectiveness: allows us to copy genes that can be used in combination with other genetic technologies to make useful products for us. describe techniques and applications used in recombinant DNA technology, for example: Recombinant DNA Technology: technology that combines two genes from different species e.g. transgenic species / genetically modified species – the development of transgenic organisms in agricultural and medical applications Transgenic Bacteria Transgenic Animals 1. Identify the desired gene from an organism 1. Identify the desired gene from an organism (e.g. insulin gene from human) (e.g. antithrombin gene from humans - stops 2. Isolate the gene by using restriction enzymes to clotting) cut it out 2. Isolate the gene by using restriction enzymes to 3. Make multiple copies of the gene using a PCR cut it out machine 3. Make multiple copies of the gene using a PCR 4. Using the same restriction enzyme to cut multiple machine bacterial plasmids in E.coli 4. Remove an embryo from an organism and 5. Use DNA ligase to paste the genes into the cut separate the cells plasmid to make multiple recombinant plasmids 5. Use microinjection to inject gene into multiple 6. Add promoter and regulator sequence to the gne zygotes (cells) to enable it to be expressed 6. Zygotes divide to form embryos 7. Use heat shock to insert the recombinant plasmid 7. These embryos are then inserted into surrogate into the bacteria to create a transgenic bacteria goats Use in medical field Use in medical field Transgenic goats born can produce antithrombin in their If successful the bacteria is able to produce human milk which is used in medicine to treat people that have insulin which is used in medication to treat people with issues with excessive blood clotting - reducing risk of a type 1 diabetes cardiovascular disease Transgenic Plant 1. Identify the Vitamin A gene in daffodils and cut it out using restriction enzymes 2. Use a PCR machine to make multiple copies of this gene 3. Cut multiple plasmids from soil agrobacterium T using the same restriction enzymes 4. Paste the Vitamin A gene into the bacteria’s plasmids 5. Use heat shock to insert plasmids back into soil agrobacterium T 6. Dip rice embryos in a solution of transgenic soil agrobacterium T 7. Bacteria will infect rice embryos inserting the Vitamin A gene from its plasmids into the rice embryos 8. Rice embryos will grow into rice plants that producer higher values of Vitamin A Use in agriculture Transgenic Bt cotton can now produce a protein that is poisonous to its main pest. Therefore the plant now requires minimal pesticides so that caterpillars are eliminated but beneficial insects are unaffected. Therefore it does not harm native animals and it is also therefore less expensive to grow with increased yield + reduces pesticide use. However it can reduce biodiversity by disrupting the food chain and outcompeting other species in the area. Or Golden rice can now have additional nutritional value - this can be given to people in third world countries to relieve hunger and reduce incidences of blindness (daffodile vitamin A Gene) To put into agrobacterium Agrobacterium infects the rice embryos Transgenic mosquitoes mating with malaria vectors, which eradicates the vector’s ability to pass on a pathogen (CRISPR-Cas9 gene-editing technology was used to make changes in mosquito genes that could reduce their ability to spread malaria. This could provide a new way to reduce illnesses and deaths caused by malaria. evaluate the benefits of using genetic technologies in agricultural, medical and industrial applications 1. Define all the subjects (genetic technology) 2. Write points for and against (providing support with examples) 3. Make a judgement of how effective genetic technology is for improving human life, animal health, environment, biodiversity Example: Modern genetic technology allows humans to manipulate the path of evolution by combining the genes of organisms that were once separate species. This has the benefit of increasing biodiversity in the short term but can decrease biodiversity if largely used. However these genetic technologies have regulations in place, have many known benefits for humans and risks are potentially not definite. Therefore the benefits outweigh the risks of using genetic technology on agriculture, medicine and industrialisation. Agriculture For Against - Potential to produce crops that are - Potential health risks of GM products are not yet not known better suited to an environment - People with allergies may have allergic reactions to foods they could (weather), disease and pest resistant previously eat if those foods include the DNA of other organisms they are and have greater output, increasing allergic to productivity e.g. BT cotton - Bt cotton has the potential to kill all caterpillars and as a result species that feed off these caterpillars reduce in population, reducing biodiversity - Artificial insemination initially increases allele frequency desirable traits in the gene pool e.g. of dairy cows. But if these same features keep on being selected, over time this will lead to decreased overall genetic diversity of dairy cows Medical For Against - Foods with higher nutritional value may be developed to - Gene therapy is still in early / experimental support people in third world countries stages and doesn’t work for all patients and - Can be used to reduce pesticide use, improving consumer side effects can lead to tumor formation health - Can be used to artificially produce medicine efficiently e.g insulin - Genes can be cloned and then used in gene therapy which involves inserting a ‘healthy’ gene into another organism's cells to replace damaged genes that cause disease. Industrial For Against - GM plants could be used to produce environmentally friendly chemicals that can - Unknown effect on replace the non-renewable products that are currently used (fuels, plastics, environment of paints) releasing/using genetically - Researchers have been working on developing genetically engineered plants modified bacteria e.g. to  and bacteria that can absorb heavy metals, such as mercury from contaminated clean oil spills / or absorb sites. This could aid in the recovery of local ecosystems that are heavily polluted heavy metals - GMO bacteria has the potential to produce enzymes that can break down oil - Biofuels still produce large and consume this oil, hence it can clean up oil spills in the ocean amounts of carbon dioxide - Sugarcane is used as a biofuel where it can be fermented to produce ethanol to into the environment, be used as a fuel for motor vehicles (renewable source of energy compared to contributing to global oil fuels) warming evaluate the effect on biodiversity of using biotechnology in agriculture Define biotechnology: - area of biology, involving the use of living systems and organisms to develop or make products - can have both a positive and negative impact on the genetic variation of individuals, populations, species - reduction in genetic variation lessens the species resilience to changes in the environment and disease, as well as reducing the ability of the environment to meet the needs of humans in the future Define a biotech What is the biotech used for Positive and negative effects of biotechnology - Reproductive tech (artificial, selection, insemination & pollination) Reduction in genetic variation due to repetitive selection of specific desired genes. E.g. Artificial insemination has allowed for the breeding of Friesian dairy cows in Africa, resulting in greater milk output and economic gain. However this strain threatened the native ankole cattle as they can outcompete native species. This is a concern as ankle cattle are well adapted to the semi arid condition of countries such as uganda and do not require great amount of water, feed or veterinary attention and therefore are well adapted to the environment - Artificial insemination and pollination can have advantages as it allows for the introduction of new genes to a population, which can increase the genetic variation in the gene pool. - Whole organism cloning poses a risk to biodiversity with the potential for multiple identical genetic copies becoming widespread in a population resulting in a loss of natural vigour. Transgenic and genetically modified species pose a significant threat to genetic variation, with threats to agriculture and the natural environment as a result of selection of a narrow range of transgenic over wild species, risk of pesticide and insect resistant species leading to invasive pests in the natural environment, reduction of non- target species such as honeybees as a result of GM - Whole organism cloning and genetic cloning has advantages for biodiversity as holds the potential to reintroduce lost genetic variation into a population restore ecosystem function as well as genetic resilience. Can also be used to increase populations of species going extinct - Can also decrease environmental impact agriculture has on the environment (BT cotton) Make a judgement - Biotechnology has led to a reduction in biodiversity - However, it should be used as it is vital to provide enough food for the growing population and can be used responsibly to maintain and even increase biodiversity  - To continue safe use of biotechnology we must implement ethical guidelines, biosafety protocols and clear legislations for genetic and animal manipulation to prevent damage to biodiversity E.g. GMOs - T - cotton effect on biodiversity - Introduce new alleles into a - Ongoing selection of this variety population, increasing genetic results in loss of other varieties, diversity reducing genetic diversity - GM cotton results in reduced use of - GM cotton reduces specie diversity by pesticides = reduced harm on reducing caterpillar population and surrounding plants and animals = other organisms that feed off increasing in biodiversity caterpillars - Can outcompete other variants, resulting in loss of genetic diversity interpret a range of secondary sources to assess the influence of social, economic and cultural contexts on a range of biotechnologies Issue: should biotechnology be used? Why biotechnology is used / should be used Why biotechnology is not used / should not be used Social - Has allowed the medical industry to improve through - Countries with health issues that do not affect the rest engineering genes to rid disease causing agents and of the world (poor countries) have little influence to mutations. This is also present in food with investigating biotechnological solutions biotechnology engineering food/diets to treat chronic E.g. ebola vaccines have not been developed as they diseases only plague developing countries - Agricultural biotech allows us to increase supply to meet - Lack of consistent regulations internationally restricts the demands of the ever growing population GM foods to be imported - Can create super foods that have higher levels of - concerns over food security & political freedom vitamins, iron, antioxidants to those who are → biotechnology may mean farmers have less malnutritioned, helping developing countries to avoid say in the crops produced, & food production anemia, blindness and other developmental issues that may be controlled by the government stem from undernutrition and deficiencies - there is a need for regulations & labelling to ensure - May help employ sustainable farming practices to consumer equity & knowledge, and until these combat climate change and environmental damage regulations are effectively implemented, biotechnology - Transgenic crops don't use pesticide → heightens may not be employed quality of life through less use of chemicals improving - ethical concerns about the exploitation of human and ecological health. animals → people do not want to use - Transgenic crops are drought resistant → water biotechnology if it harms animals conservation - potential for environmental damage via an increase in monocultures, loss of habitats & biodiversity. - environmental restoration and the management of Eg. use of insecticide-containing GMOs impact non- endangered species and ecosystems; for example, the harmful insects & the food chain. If herbicide-tolerant collection of coral sperm and eggs at Heron Island to genes escape into weed populations, there is potential help regenerate coral reef for weed problems to escalate. Economic - Can increase efficiency of farming, pharmaceuticals and - Economies with rich biodiversity may want to protect industrialisation, decreasing costs to consumers, against the use of biotechnology to maintain the high increasing profits made by companies rates of gene frequencies, therefore reducing the use  - Economies with rich biodiversity are more likely to have of biotechnology specie varieties with advantageous products that can be E.g. Philippines banned the import of GM soybeans useful in the medical field, improving quality of life - Large companies often hold the license to grow their E.g. The Philippines has rich biodiversity that has led to developed GM products. Therefore this decentifies the third largest pharmaceutical market in the world. small farmers from using this biotechnology as it - May provide farmers in third world countries with tools reduces profits due to paying rights to grow these to grow crops easily and quickly products - Enables farmers with nutrient-poor soil or poor access - Potential for monopolisation by large biotechnology to water to continue growing nutrient-rich foods, and companies, cutting small scale farmers out of the increasing foot output global market in third world countries, creating a - Can reduce poverty in developing countries through greater gap in income inequality (socioeconomic growing of GMOs that are more efficient and therefore disparity) more affordable E.g. Developing countries traditionally export E.g. Golden rice to feed malnutritioned in Africa resources such as palm oil, vanilla and rubber. But without GM products they may lose their international competitiveness in the market Cultural - Food is an important element of different cultures. - Traditional, region-specific farming practices may be Therefore different societies may be inclined to use eradicated in favour of large-scale agricultural methods biotechnology to preserve their cultures signature dish E.g. loss of important parts of indigenous cultures and maintain significant industries in certain areas - Cultural concerns that GM taro may reduce the purity E.g. Taro is sacred in the Hawaiian culture but over the of the taro, alter the food’s identity, reduce the last century taro has been reduced due to taro leaf biodiversity of taro, removing the option to grow blight disease but GM taro has the potential to be different variants of taro disease resistant - Backlash from conservative \ certain religious groups - Biotechnology can be used to adapt to changing on ethical grounds. environments E.g. in isalm eating pork is prohibited, therefore there - Less environmental damage because of efficient food are concerns of pig genes into food sources or in production. This is because some indigenous cultures organ transplants, no longer allowing them to use have sacred land these foods E.g. golden rice could be produced instead of normal rice which takes up less room as it has higher nutritional value and therefore damages less land