Genome Projects and Gene Technologies Flashcards
(43 cards)
why is the probability of 2 individuals having same GFP low?
chance of 2 individuals having same number of VNTRs at each place found DNA is low
what does electrophoresis do?
separates DNA fragments to make GFP
process of electrophoresis
- DNA is extracted from tissue and amplified using PCR
- the DNA is cut into fragments using same restriction endonucleases
- fluorescent tag added to all DNA fragments
- DNA mixture placed in well of gel and covered in buffer solution - conducts electricity
- electrical current passed through gel - DNA fragments neg charged —> move towards positive electrode
- a set of bars is revealed using the markers on the probes
- the pattern is unique to each individual, except for identical twins
what is GFP used to determine?
- genetic relationships
- genetic variability within population
- forensic science
- medical diagnosis
how do you make paternity tests more accurate?
higher number of places in genome compared
what are sarcomas?
type of tumours
in PCR, why is the sample of DNA heated to above 90 degrees?
production of single stranded DNA
in PCR, why are primers added?
- complementary to start and end of gene
- replication of base sequences from here
in PCR, why is polymerase from bacteria that live at high temps used?
- enzymes not denatured at high temps
- allows rapid replication of DNA
one cycle of PCR takes 5 mins.
starting with a single gene, calc the number of copies of the gene produced in 40 mins?
256
give advantages of producing genes via genetic enginering?
- large scale
- cheap
- easier prod of human proteins etc
suggest reasons why people may be concerned about using genetic engineering?
- long term effects unknown
- ethical issues
- may spread antibiotic resistancy
- wrong to experiment on animals
- may encourage similar research using cells from human embryos
describe how a gene can be isolated from human dna?
- use restriction enzyme
- to cut DNA in specific base sequence
describe how an isolated gene can be replicated by PCR?
- heat DNA to 90-95 degrees C
- strands separate
- add primers
- add nucleotides
- cool so primers bind to DNA
- DNA polymerase forms new strands/ joins new nucleotides
describe one example of use of PCR?
- provides multiple copies of DNA fragment
- e.g. analyse in forensic detection
explain the role of DNA polymerase in RT-PCR?
joins nucleotides to produce complementary strands of DNA
any DNA in the sample is hydrolysed by enzymes before the sample is added to reaction mixture.
why?
- to remove DNA present
- as this DNA would be amplified
sugggest one reason why DNA rep stops in PCR?
limited number of primers for use
scientists have used RT-PCR method to detect the presence of different RNA viruses in patients suffering from respiratory diseases.
the scientists produced a variety of primers for this procedure.
why?
- base sequence differs
- different comp primers required
process of GFP?
- DNA extracted from sample
- DNA hydrolysed into fragments using same RE
- DNA fragments separated using electrophoresis
- mixture put into well of gel and electric current passed through
- immerse gel in alkaline sol
- cover with nylon
- DNA fixed to nylon using UV light
- radioactive marker added
- areas with probe identified using X-ray film
describe how scientists could genetically engineer clostridium bacteria to produce the enzyme which activates the prodrug?
- cut gene out of cell
- cut DNA using RE
- cut sometimes prod sticky ends
- joind DNA using ligase
- plasmid transferred into cell
- bacteria forced to uptake DNA by heat shock
- add marker gene
- select bacteria containing new gene
how could GFP from test indicate that a person is father of child
bands in baby that dont come from father come from mother
how can GFP be useful in selecting animals for breeding
pairing animals with dissimilar fingerprints
explain why Taq1 cuts normal allele in 4 places but only cutes mutant allele in 3 places
- Taq1 cuts at specific sites
- no longer present
