genetic technologies Flashcards
(109 cards)
1
Q
what is the genome
A
all the genetic info in an organism or cell
2
Q
how is the genome sequenced
A
cutting the DNA into fragments which are sequenced and them put back into the correct order to give the whole genome
3
Q
what are genome projects
A
use technology to determine the complete sequence of bases that make up the DNA of an organism
4
Q
how can sequenced genomes be used in biology
A
-compare with particular species to highlight disease risk or identify mutations which cause disease - so can gte early diagnosis and treatment
-comparision of genomes between speceis can be used to explain the evolutionary relationships between species and used to build phylogenetic trees
5
Q
what is bioinformatics
A
science of collecting and analysing complex biological data such as genomes
6
Q
what is the proteome
A
sequence of protiens coded for by the DNA base sequence in the genome at a given time
7
Q
how can the proteome be determined
A
by sequeceing the genome
8
Q
why is finding the genome of prokaryotes easier than eukaryotes
A
-only have one circular length of DNA - cDNA
-no non-coding regions
9
Q
how has sequencing the proteome advance medicine
A
-produce vaccines faster
-monitor mutations
-nonitor variations as the pathogen evolves
-idnetify antibiotic resisitance mechanisms
10
Q
why is eukaryote genome more difficult to sequence
A
-has introns which need to be removed
-these are non-coding - ie junk DNA or regulatory genes (switch on/off coding regions)
-make up 98.5% of DNA
11
Q
what was the human genome project
A
In the 1980s Cambridge scientists had been working on sequencing the genome of a nematode. As they progressed they realised that the technology used in this research could be applied to the human genome
The Human Genome Project (HGP) began in 1990 as an international, collaborative research programme
It was publicly funded so that there would be no commercial interests or influence
DNA samples were taken from multiple people around the world, sequenced and used to create a reference genome
Laboratories around the globe were responsible for sequencing different sections of specific chromosomes
It was decided that the data created from the project would be made publicly available
As a result, the data can be shared rapidly between researchers
The information discovered could also be used by any researcher and so maximised for human benefit
By 2003 the human genome had been sequenced to 99.9% accuracy
The finished genome was over 3 billion base pairs long but contained only about 25,000 genes
This was much less than expected
Following the success of sequencing the human genome scientists have now moved onto sequencing the human proteome
The proteome is all of the proteins that can be produced by a cell
Although there are roughly 25,000 genes within the genome there are many more proteins within the proteome. This may is due to processes such as alternative splicing and post-translational modification
There is also work being done on the human epigenome
These are the inherited changes in DNA that do not involve a change in DNA base sequence
12
Q
what is DNA sequencing
A
process of determining the sequence of nucleotides in a piece of DNA
13
Q
what was Sangers technique to sequence DNA
A
-1977
-very basic - used radioactive bases as the stop base
-then X-ray and view by hand
-more complicated and time consuming
14
Q
what is the modern process of Sanger sequenceing
A
-primer binds to the DNA
-DNA polymerase can make the new DNA by adding nucleotides to the growing chain
-this happens unitl by chance it add a coloured dideoxy nucleotide - meaning it lacks a OH
-this is labbelled as the final positon
-fragments are run through a matrix calld gel electrophoresis which sperates the fragments by size
-short fragments run quickly, long fragments more slowly
-exposed to laser allowing the colours to be detected - so allowing the last nucleotide in the chain to be detected
-from the colurs of dye emitied by the chain terminating nucleotide, the orginal sequence of DNA can build up one nucleotide at a time
15
Q
how has DNA sequencing changed
A
-made cheaper
-more cost-effective
-large scale
-faster
16
Q
how many bases are there in the human genome
A
3.2 billion
17
Q
what is genetic engineering
A
process where a gene from one organism is insterted into the genome of another - so it has the desired characteristic
18
Q
how does genetic engineering work
A
-useful gene is identified
-useful gene is cut form the DNA using enzymes
-the gene is inserted into a plasmid vector
-plasmid containing the desired gene is inserted into the bacteria so it can multiply
19
Q
give 3 examples of organisms that have been genetically modified
A
-bacteria - useful subastances such as human insulin
-food crops - improve yield,better resistance to disease/pests
eg Bt Cotton has resisatance to a specific catipillar pest
eg Golden rice - improve vitamin A - beta-carotene which is converted to vitamin A in the body
-sheep -produce useful bacteria/vitamins in thier milk
20
Q
what are the benefits of GM organisms in medicine
A
-can produce large amounts of protiens like insulin and other drugs very fast
-human insulin made this way will not be rejected by the body
-it will allow treatment for some human genetic disorders in the future
21
Q
what are the negatives of GM organisms in medicine
A
-very expensive
22
Q
what are the benefits of GM crops
A
-resistant to pests and diseases whihc allow plats to gorw better and increase the yield
-produce more food
-produce more nutritious food in places that they cant grow lots
-reduce the use of chemical pesticides
23
Q
what are the negatives of GM crops
A
-inserted genes could be transferred to wild/natural pop of plants which could affect biodiversity of the plants and insects that feed on them
-especially resistant genes could stop farmers being able to control the growth of weeds and other plants
-some people have objections as they believe it is not natural
-has the effects of eating GM crops been studied enough in humans?
24
Q
what are the 5 stages of gene cloning and transfer
A
- isolation- DNA fragment that has the desired gene for the desired protien
- insertion- DNA into a vector
- transformation- DNA vector into the host cell
- identification- id which host cells have actually taken up the gene - using gene markers
- cloning/growing- host cell into the product
25
how can GMOs be used in making proteins
-will produce purer, less chance of rejections and cheaper than extraction from an animal donor
-genetic code isuniversal so the GMOs make the same protein as the original donor
26
what are the 3 ways to isolate gene fragments
1. using reverse transcriptases to make DNA from mRNA
2. using restriction enzymes to cut a section of DNA from the genome
3. using a gene machine to build a section of DNA using nucleotides
27
how does using reverse transcriptase to make mRNA/cDNA work
-mRNA will be comp to the target gene
-reverse transcriotase is added and uses free DNA nucleotides to make cDNA from the mRNA template
-single stranded cDNA is isolated by the hydrolysis of the mRNA using an enzyme
-double stranded DNA is formed from the cDNA using DNA polymerase
-giving a copy of the gene
28
what is cDNA
-comp DNA to the mRNA
29
how does using restriction enzymes to cut a section of DNA from the genome work
-restriction endonucleases/enzymes will separate the two strands of DNA at the specific base sequence - that is comp to their active site-
-cut the sugar phosphate backbone in an uneven way to give sticky ends or straight blunt ends
-each restriction sequence is palindromic - comp to one and other - read same in each direction
30
what is the role of sticky ends
-result in one DNA strand being longer than the other
-makes it easier to insert the desired gene into another organims DNA
-easily for H-bonds with the comp base sequences on the other pieces of DNA that have been cut with the same restriction enzyme
31
what are restirction enzymes/endonucleases
-class of enzymes found in bacteria
-recognise and hyrdolyse hydrogen bonds at specfic sequences of DNA
32
how does using a gene machine to build a section of DNA using nucleotides work
-if sequence of AA is already known the sequence of comp base triplets can be found out
1. base sequence is fed into a computer once it has been checked for biosafety and secrutiy
2. nucloetides added step by step in the right order and joined in the correct place to prevent branching
3. short sections of DNA called olginucleotides are produced - 20 long - these can be joined by DNA polymerase to form longer fragments
4. no introns or non-coding info in the gene as it has been sequenced from the final protien - so already undergone splicing
5. PCR is used to replicate the gene and make it doubl stranded
6. sticky ends added
7. gene can be insterted into a vector
33
why is using a machine often the preffered method to isolate DNA
-alot quicker than using lots of enzymes
34
what is in vivo gene cloning
-in the living - in whole,organisms or cells
-DNA fragment is placed in a plasmid and relies on bacteria conjugation and replication to make a copy of the plasmid
-takes longer and requires screening as not all bacteria will take up the gene
-using maker genes and manipulating growth conditions can help determine if genes have been taken up and amplified by the organism
35
what are the 5 stages of in vivio gene cloning
-desired gene is isolated using a restriction enzyme
-gene is inserted into a vector using a plasmid-
-recombinant plasmid is now tranaferred to host cells -transformation
-host cells are allowed to multiply and those that have taken up the genes are identified using a marker gene - indentification
-cloning/growing
36
how does the 1st stage/isolation of the gene using a restriction enzyme work
-promoter region and terminator regions are added to the gne to make sure the gene can be correctly transcribed once in the host
-promoter - tells RNA polymerase where to start transcribing mRNA
-terminator - tells RNA polymerase to stop
37
what is the 2nd stage/ gene is inserted into a vector
-plasmids - which are circular lengths of DNA, found in mos t bacteria that are seperate from the main DNA - contain genes for antibiotic resistance
-cut the plasmid with the SAME restriction enzyme to leave sticky ends - comp to DNA fragment and plasmid
-DNA ligase enzyme joins the two DNA fragments together - catalyse the condensation reactions that join sugar and phosphate group
38
how can the gene be inserted into the plasmid wrongly
-gene can go in backwards
-plasmid can close back up - without gene in- sticky ends close
39
how does the 3rd stage/ the recmobinant plasmid is transferred to the host cell work
-solution of calcium ions can be used to make the cell walls more permeable
-heat shock or electroporation (small electric shock) is used to make holes in the membrane which DNA can pass through
-some bacterial cells wont take up the plasmids
-only bacteria whihc now contain the recombinant plasmid will be able to express the gene and make the protein
40
what are the 3 ways that stage 4/ identification using marker genes can be done
-using antibiotic resistant genes
-genes coding for fluorescent proteins
-genes coding for enzymes
41
how does using antiobiotic resistance genes to identify genes work
-marker genes can code for antibiotic resistance
-colonies of bacteria are grown on an agar plate that contains the antibiotic
-only transformed genes with the resistant gene will survive
-they can then be selected
-take a copy of the agar with bacteria on
-transfer onto a plate that has an antibiotic on - those with resistant gene will not be killed
-restamp this and grow on another plate that has antiobiotic on
-the ones that are killed this time will be the ones resitant to the previous AB and not this one
-so can then look back at the original and identify which has resistance
42
how does genes coding for fluorescent proteins as markers work
-gene from jellyfish that contains a green floruescent protein is insereted into a plasmid
-the gene to be cloned is inserted into the centre of the GFP gene
-restriction enzymes cut and put the gene in a vector - destroys the ability for the fragment to grow
-bacterial cells that have the recombinant pasmid - will not fluoresce
-bacterial cells with the non-recombinant plasmid - will fluoresce
43
how does using genes coding for enzymes as marker genes work
-enzyme lactase can turn certain substances from colourless to blue
-the gene for this enzyme is inserted into a plasmid
-the DNA fragent is inserted in the middle of this gene to disrupt it
-the bacteria are then grown on an agar plate with the colourless solution
-the colonies which cannot turn the colourless substance bluw contain the recombinant plasmid
44
how does stage 5 in in vivo cloning work
-genetic code is universal so bacteria can transcribe the DNA and transalte the mRNA to produce the protien
-the mechanism and machinery is the same in all organims
-a fermenter is used to grow multiple copies of the host cell which have been indentified as containing the copy of the recombinant plasmid
-the clones can then produce the protein coded for by the inserted DNA fragment
45
what is in vitro cell cloning
-DNA replicated in a lab using a machine
using the polymerase chain reaction
46
how does in vitro cell cloning compare
to in vivo in terms of speed
-makes millions of copies in a matter of hours compared to in vivo which can take days
47
what is PCR
-artificial repliaction of short - up to 10000 base pairs - of DNA sequences
-carried out in a thermocycler to replicate them many times in a way that is simialr to DNA rep in the nucleus
48
what is required for PCR to work
-target DNA or RNA being amlified
-primers
-DNA polymerase - in this case use Taq Polymerase from a bacteria
-free nucleotides
-buffer solution
49
what are primers and why are they used in in vitro
-short sequences of single stradned DNA comp to the 3' end of the DNA being copied - define the region that is too be amplified by identifying to the DNA polymerase where to begin building the new strands
50
why is Taq Polymerase used in in vitro
-does not denature at high temp as is thermophilic
-optimum temp is high enough to prevent annealing of the DNA strands that have not been copied yet
51
what are the 3 stages of PCR
-denaturation
-annealing
-elongation/extension
52
what is the denaturation stage of PCR
-double stranded DNA is heated to 95 degress which breaks the hydrogen bonds that bond the two DNA strands together
53
what is the annealing stage of PCR
-temp decreased to 50-60 degrees so that primer - both forward and reverse ones - can anneak to the ends of the single strands of DNA showing the Taq polymerase where to bind
54
what is elongation/extension stage of PCR
-temp increased to 72 degrees for at least a minute
-as this is the optimum temp for taq polymerase to build the comp DNA strands by comp DNA nucleotides base pairing
-creates 2 identical strands
55
what is the formula to calculate how many dna nucletoides have been produced in a cycle
1 x 2 ^ number of cycles
56
how to describe the PCR graph
-the curve
-DNA is doubling at each cycle but there are very low numbers at the start, so little fluoresence is detected so it appears flat and then exponential growth occurs as numbers rapdily increase
-why it levels off
-primers are the only thing to be used up in the reaction so this limits the number of fragments that can be made
-when they run out replication stops
-it could also be nucleotides running out but this is less likely
57
what is recombinant DNA
DNA that has been altered by introducing nucleotides from another source
58
what is an organism called if it contains nucleotides from a different species
transgenic
59
what is a genetically modified organism
an organism that has introduced genetic material
60
what are recombinant protiens
-manipulated forms of the original protein
-generated using microorganism such as bacteria, yeast or animal cells in culture
-used for research processes
-most human recombinant proteins use eukaryotic cells as these cels will carry out post-translational modification - due to golgi - that is required to produce a sutiable protein
61
what are the advanatges of using genetic engineering organisms to produce recombinant proteins
-More cost-effective to produce large volumes (i.e. there is an unlimited availability)
-Simpler (with regards to using prokaryotic cells)
-Faster to produce many proteins
-Reliable supply available
-The proteins are engineered to be identical to human proteins or have modifications that are beneficial
-It can solve the issue for people who have moral or ethical or religious concerns against using cow or pork produced proteins
62
what is gene therapy
using mechanisms to alter a persons genetic material to treat or cure disease
-many gene therapies are still in the clinical trial stage - finding new delivery systems is difficult
-they all have been targeted and tested on somatic - body - Changes in genetic material are targeted to specific cells and so will not be inherited by future generations (as somatic gene therapy does not target the gametes)
63
what are scientists able to do with gene therapy
replace a faulty gene, inactivate a faulty gene or insert a new gene
64
what are the 2 types of somatic gene therapy
-ex vivo
the new gene is inserted via a virus vector into the cell outiside the body
blood or bone marrow are extraced and exposed to the virus which insertes the gene into these cells - these cells are then grown in the lab and returned to the body by injection into the vain
-in vivo
new gene is inserted via a vector into the cells inside the body
65
what are some of the social and ethical consideration associated with gene therapy
-The potential for side effects that could cause death (eg. the children who were treated for SCID developed leukaemia)
-Whether germline gene therapy (the alteration of genes in egg and sperm cells which results in the alteration being passed onto future generations) should be allowed – it could be a cure for a disease or it could create long-term side effects
-The commercial viability for pharmaceutical companies – if it is a rare disease, the relative small number of patients may not mean that the companies will make a profit (eg. Glybera – a gene therapy for lipoprotein lipase deficiency is no longer produced as there were too few patients)
-The expense of treatments as multiple injections of the genes may be required if the somatic cells are short-lived (eg. severe combined immunodeficiency). This may make the cost of gene therapy accessible to a limited number of people
-The possibility that people will become less accepting of disabilities as they become less common
-Who has the right to determine which genes can be altered and which cannot (eg. should people be allowed to enhance intelligence or height)
-Another method of enhancing sporting performances unfairly through gene doping. This is where the genes are altered to give an unfair advantage eg. to provide a source of erythropoietin (the hormone that promotes the formation of red blood cells)
66
what are GM crops used for
-crops can be
-resistant to herbicides to increase productivity and yeild
-resistant to pests to increase productivity and yeild
-enriched in vitamins to increase the nutiritonal value
-animals can be
-gorw faster - for food production - ethical concerns
-resitance to certain diseases / increased nutiritional value
67
benefits of GM crops/animals compared to traditional selective breeding
Organisms with the desired characteristics are produced more quickly
All organisms will contain the desired characteristic (there is no chance that recessive allele may arise in the population)
The desired characteristic may come from a different species / kingdom
68
social and ethical implicatiosn of GM in crops/animals
The genetic modification of microorganisms for the production of medicines, antibiotics and enzymes raises little debate compared to the use of genetically modified organisms (GMOs) for food production
The use of GMOs in food production has been proposed as a solution to feeding the increasing world population, the decreasing arable land and decreasing the impact on the environment, however concerns such as the development of resistance in insects and weeds and costs of seeds have meant that countries are not allowing GMOs to be grown
The solution could be integrated pest-management systems that could help avoid the development of resistance and increased population of secondary pests
The ethical implications of using GMOs in food production are:
-The lack of long-term research on the effects on human health – should GM food be consumed if it is unknown whether it will cause allergies or be toxic over time (although there has been no evidence to suggest this would occur to date)
Making choices for others:
-That without appropriate labelling the consumer cannot make an informed decision about the consumption of GM foods
-As the pollen from the GM crop may contaminate nearby non-GM crops that have been certified as organic
-By reducing the biodiversity for future generations
The social implications of growing GMOs for food evolve around whether the crops are safe for human consumption and for the surrounding environment
The possible implications are:
-The GM crops may become weeds or invade the natural habitats bordering the farmland
-The development of resistance for the introduced genes in the wild relative populations
-Potential ecological effects (e.g. harm to non-targeted species like the Monarch butterflies)
-Cost to farmers (new seed needs to purchase each year)
-The ability to provide enriched foods to those suffering from deficiencies (eg. Golden Rice) and therefore decrease diseases
-Reduced impact on the environment due to there being less need to spray pesticides (eg. less beneficial insects being harmed)
-Reduction in biodiversity which could affect food webs
-The herbicides that are used on the GM crops could leave toxic residues
69
what are variable number tandem repeats
repetitive non-coding bases on the DNA
70
by which method are substances separated
-gel electrophoresis
-electrical gradient is set up and samples are loaded onto agar gel to slow them down
-drawn to the postive electrode as the subastances are negativley charged
-seperate by size/length and charge
71
72
what substances are separated by gel electrophoresis
DNA, RNA and proteins
as these are polar
73
why is a control group used in gel electrophoresis
-known length
-so comparisons can be made and the size of the frgaments of DNA can be determined
74
what are the stages of gel electrophoresis
-extraction
-digestion
-separation
-hybridisation
-development
-interpretation
75
what happens in the extraction stage of GE
-DNA fragments whihc have been amplified using PCR are mixed with a loading buffer and pipetted into the wells of an agar gel
76
what happens in the digestion stage of GE
-DNA is cut into fragments using the same restriction endonucleases
77
what happens separation stage of GE
-frgaments are separated by GE using an electrical voltage - an alkaline buffer is added to separate the two strands of DNA into single strands
-smaller fragments mirgrate the furthest as they are lighter/have fewer bases
78
to which end do the fragments migrate too
-positive as opposite charges attract
79
what happens in the hybridisation stage of GE
-radioactive or fluorescent probes are added which are comp to certain lengths of DNA
-these bind to the VNTR
80
what happens in the development stage of GE
-gels are removed from the tank and photographed under UV light - for flourescent probes
OR
-audiography - for radioactive probes
81
what happens in the interpretation stage of GE
-a series of bands are revealed
-this band pattern is unique to that person/organism
82
how is a sample prepped for genetic fingerprinting
-restriction endonucleases are used to make DNA fragments that contain VNTR - these may be amplified using PCR
-DNA fragments are spearated by size using GE
-compare DNA fragments/proteins next to known sample
83
how is genetic fingerprinting used in medical diagnosis
-testing to see if the cause of symptoms is a genetic disease eg huntingtons - run gel known against H DNA
-most useful when specific mutation which causes the disease is known eg BRCA1 linked to breast cancer - prevents embroys being implanted that have the mutated allele
84
how is genetic fingerprinting used in forensics
-establish if a person was present at the crime scene if they left a biological sample containing DNA
-identify and narrow down subjects
-more bands the person has then the more likely they are to be the suspect
85
how is genetic fingerprinting used in
determining genetic relationships
-paternity tests or identifying siblings
-childrem have more bands in common with thier parents as they will have inherited 50% of their VNTR
-siblings - more bands in common - closer related they are
-it can be used to identify the relatedness of different populations often using mtDBA which is only inherited from mother or Y chromosometo trace paternal inheritance only
86
how is genetic fingerprinting used in genetic variabilitly
-determine genetic variabiltiy within a pop
-very similar genetic fingerprints = less genetic diversity
87
how is genetic fingerprinting used in animal and plant breeding
-determining paternity and therefore pedigree of animals
-identifying plants or animals with a desired allele or gene
-prevents inbreeding which increases risk of genetic disorders
-allows pedigree of award winning animals to be determined
88
does everyone have similar VNTR or not
-no -diiferent
-however closely related people will similar VNTR
89
what are the uses of gene probes
-locate specific alleles of genes
-see if a person carries a mutated allele that causes a genetic disorder
-help determine how patients will respond to drugs
-identify health risks associated with drugs
90
what are gene probes
-single-stranded pieces of DNA which are comp to and therefore bind to known base sequences
-DNA probes can be used to hybridise with comp DNA
-labelled with a radioactive marker or a fluorescent marker which is more common
91
what is the method of making DNA probes
-single stranded DNA probe is made using PCR - it has a base sequence comp to part of the DNA sequence of the target allele - the probe is labelled
-test DNA cut using a restriction enzyme
-separated by mass/length using gel electrophoresis
-bands of DNA transferred to a nylon membrane
-these are made to be single-stranded - break hydrogen bonds bwt base pairs
-labelled probes added to the nylon membrane - comp to the harmful allele
-unattached DNA probes are washed off
92
how can microarrays be used to identify probes
-sample of fluorescent DNA is washed over the array which has the DNA probes fixed to it
-DNA sequences that match to the probe stick to the array
-they array is washed to remove any fluorescent` DNA not stuck to a probe
93
what types of genetic disorders can be screened for
recessive - can be carriers - not dominant ones
94
what is genetic counselling
-make informed decisions about matters related to genetics that may come in peoples health
-decisions can be made based on the outcome of the counselling
-helps people to consider the chances but also the emotional, psychological, medical, economic and social implications of having an affected child
-use screening to explain chances of getting cancer
95
what is personalised medicine and why is it useful
-target different dosages or compounds as medicine depending on the genetic make-up of the person
-makes drugs more cost effective, safe and effective
-dosage- genes may affect effectiveness of the drug
-some drugs can vary depending on genotype - so need to be screened to ensure which is safe to sue
96
what is the basic principle of gene therapy
-insert a functional allele of a particular gene into the cells that contain only mutated and non-functional alleles of that gene
-if the inserted allele is expressed will produce a functioning protein and no longer have the symptoms associated with the genetic disorder
97
what are somatic cells
body cells
98
what is somatic gene therapy
-affects only cells of a certain type
-alterations made are not passed on to offspring so vulnerable ti the disease
99
how is cystic fibrosis treated
-liposomes are placed into an aerosol inhaler and sprayed into the noses of patients
-some liposomes will pass throiugh the plasma membrane of the cells lining the respiratry tract
-some liposomes will then pass through the nuclear envelope and insert into the host genome
-the host cell will express the CFTR protein
-needs to be done every 2 weeks as the cells lining the epitheilial cell replace themselves every 10-14 days
100
what is cystoic fibrosis
mucus build up due to the lack of CFTR protein
-so water doesnt flow back as chloriune ions cannot pass thorugh
-so mucus not diluted
101
how can viral vectors be used in gene therapy
attenuated virus used as a vector to deliver functional gene copy
-human DNA replaces the viral DNA
-problems - not known whether gene will get into the lung cells before it is destroyed by the body's immune system thinking it is foreign - could be toxic or inflammatory
102
what is germline gene therapy
alters gamete or zygote of the organism
-potential to alter the genetic make-up of the descendants of the person
-no descendent gives consent and there may be concerns over how the gene is inserted
-strict guidelines are drawn and there are a lot of ethical issues needed to be thought abt
103
what are the positives of gene therapy on animals
-genetic manipulation is no different from crossbreeding - domestic farm animals today are not closely related to their wild ancestors
-genetic manipulation reduces cost and increases pop of crops for people
104
what are the negatives of gene therapy on animals
-animals are sentient
-genetic manipulation reduces the variation within the pop this is because clones are used
-there could be health implications for the animals involved
105
what are the positives of gene therapy on plants
-plant pathogens can reduce crop yeild by 10-20 % - can be up to 100% if crops arent resistant - causes famine and economic hardship - so having resistance will reduce this
-reduces cost and increases production of plant crops
-no evidence that any genes escaping crop plants that are grown in the wild
106
what are the negatives of gene therapy in plants
-plants are harder to contain than animals and these can breed with wild varieties releasing new genes with unknown effects into the environment
-potential harm to humans health through food damage
--ve impact on traditional farming practice
-excessive corporate dominance - one crop could initiate a monopoly
107
what are the positives of gene therapy in bacteria
-bacteria can be seen as little machines rather than parts of a larger ecosystem
-bacteria swap their DNA amongst themselves all the time via plasmids
-many lifesaving drugs can be produced from GM bacteria
-these bacteria can be completely contained in the lab
108
what the negatives of gene therapy in bacteria
-there is a danger that they will escape from the lab
-there could be contamination from the other products of the bacteria
-antibiotic resistance genes are used and these could create an untreatable pathogen as they are carried on the plasmid that can be shared bwt species of bacteria
109
Determining the genome of the viruses could allow scientists to develop a vaccine.
Explain how.
1.(The scientists) could identify proteins (that derive from the genetic code)
OR
(The scientists) could identify the proteome;
2. (They) could (then) identify potential antigens (to use in the vaccine);
