27. DNA technology applications Flashcards
Whar are the main fields where DNA technology can be used?
Explain the mechanism of In-Situ hybridisation
- An RNA/DNA of desired gene sequence is added a fluorescent marker
- It binds complementary to regions of the DNA in sample → where the desired gene is located found by fluorescence
Explain the mechanism of reverse transcriptase PCR and qPCR
- RNA → DNA
- PCR to amplify the desired gene
- Run gel electrophoresis to observe if the gene was present
- qPCR - measure how much of desired sequence is in the sample by fluorescence
What is the mechanism of microarrays
- Take two RNA samples, place dots of sample on the microarrays and compare them
- Taken microarrays qPCR (RT-PCR) with fluorescent bases - bind to complementary parts → visually seen which mRNAs where present in the sample
Explain the mechanism of RNA sequencing
- Take RNA
- Cut it up into small fragments
- Reverse-transcriptase into cDNA
- cDNA sequenced → sequences mapped on to the genome by computers → which genes were expressed in the taken mRNA sample?
What are the techniques fro gene analysis?
What are the possible techniques to modify genes or their expression?
Explain the mechanism of CRISPR technology
- Cas9 protein binds to the repeated palindromic sequence → complementary binds the gene from the virus (aqcuired as immune response in bacteria) or the desired sequence in the lab
- Cas9 proteins cuts the target gene
- DELETION: random nucleotides will bind to the cut sequence → no longer works
- REPAIR TO TEMPLATE: add double stranded DNA which matches as a template for the obtained sequence
Sumamry of gene and gene expression modification analysis
What are the technologies of organismal cloning?
- Micropropagation
- Nuclear transfer
Explain micropropagation
Explain how animals are cloned
- Nuclear transfer
2.
Whata re the ethical issues involved with cloning animals?
- Many die in the process of cloning
- Many are defected
Organismal cloning summary
What are the main fields of medicine where DNA technology can be used?
Explain stem cells
What are the uses of stem cells in medicine?
Pluripotent stem cells are not used currently but are in research
What are the sources of stem cell sin medicine?
What are induced ploripotent stem cells?
What is an alternative of using stem cells from embryos or iPSCs?
Transdifferentiation
(3 transciption factors used to revert)
The summary of stem cells in medicine
What are the possible uses of DNA technology in forensics?
What is Restriction Fragment Length Polymorphism (RFLP)? What is the mecganism
Equivalent to DNA fingerprinting
- Cut the DNA sample with restriction enzymes
- Between individuals the sample cut into different lengths because different repeats
What is short tandem repeats (STR)? Exlpain the mechanism
The number of STR varies between individuals → can be used to identify the person
- PCR used to amplify the sample
- PCR samples got in different numbers because of different STR → gel identified → compared with the sample from the crime scene
What is the use of DNA sequencing in forensics? What are the mechanisms?
DNA technology in forensics summary
Key learning outcomes of DNA technology applications
