27. DNA technology applications

Question 1

Whar are the main fields where DNA technology can be used?

Question 2

Explain the mechanism of In-Situ hybridisation

Answer 2

1. An RNA/DNA of desired gene sequence is added a fluorescent marker
2. It binds complementary to regions of the DNA in sample → where the desired gene is located found by fluorescence

Question 3

Explain the mechanism of reverse transcriptase PCR and qPCR

Answer 3

1. RNA → DNA
2. PCR to amplify the desired gene
3. Run gel electrophoresis to observe if the gene was present
4. qPCR - measure how much of desired sequence is in the sample by fluorescence

Question 4

What is the mechanism of microarrays

Answer 4

1. Take two RNA samples, place dots of sample on the microarrays and compare them
2. Taken microarrays qPCR (RT-PCR) with fluorescent bases - bind to complementary parts → visually seen which mRNAs where present in the sample

Question 5

Explain the mechanism of RNA sequencing

Answer 5

1. Take RNA
2. Cut it up into small fragments
3. Reverse-transcriptase into cDNA
4. cDNA sequenced → sequences mapped on to the genome by computers → which genes were expressed in the taken mRNA sample?

Question 6

What are the techniques fro gene analysis?

Answer 6

Question 7

What are the possible techniques to modify genes or their expression?

Answer 7

Question 8

Explain the mechanism of CRISPR technology

Answer 8

1. 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
2. Cas9 proteins cuts the target gene
3. DELETION: random nucleotides will bind to the cut sequence → no longer works
4. REPAIR TO TEMPLATE: add double stranded DNA which matches as a template for the obtained sequence

Question 9

Sumamry of gene and gene expression modification analysis

Answer 9

Question 10

What are the technologies of organismal cloning?

Answer 10

1. Micropropagation
2. Nuclear transfer

Question 11

Explain micropropagation

Answer 11

Question 12

Explain how animals are cloned

Answer 12

1. Nuclear transfer
   2.

Question 13

Whata re the ethical issues involved with cloning animals?

Answer 13

1. Many die in the process of cloning
2. Many are defected

Question 14

Organismal cloning summary

Answer 14

Question 15

What are the main fields of medicine where DNA technology can be used?

Answer 15

Question 16

Explain stem cells

Answer 16

Question 17

What are the uses of stem cells in medicine?

Answer 17

Pluripotent stem cells are not used currently but are in research

Question 18

What are the sources of stem cell sin medicine?

Answer 18

Question 19

What are induced ploripotent stem cells?

Answer 19

Question 20

What is an alternative of using stem cells from embryos or iPSCs?

Answer 20

Transdifferentiation

(3 transciption factors used to revert)

Question 21

The summary of stem cells in medicine

Answer 21

Question 22

What are the possible uses of DNA technology in forensics?

Answer 22

Question 23

What is Restriction Fragment Length Polymorphism (RFLP)? What is the mecganism

Answer 23

Equivalent to DNA fingerprinting

1. Cut the DNA sample with restriction enzymes
2. Between individuals the sample cut into different lengths because different repeats

Question 24

What is short tandem repeats (STR)? Exlpain the mechanism

Answer 24

The number of STR varies between individuals → can be used to identify the person

1. PCR used to amplify the sample
2. PCR samples got in different numbers because of different STR → gel identified → compared with the sample from the crime scene

Question 25

What is the use of DNA sequencing in forensics? What are the mechanisms?

Answer 25

Question 26

DNA technology in forensics summary

Answer 26

Question 27

Key learning outcomes of DNA technology applications

Answer 27