8.4.3 Genetic Fingerprinting Flashcards
1
Q
Describe and explain the full process of genetic fingerprinting and screening
A
- Add restiction endonuclease to DNA sample
- Use PCR to replicate fragments
- Seperate fragments using gel electrophoresis
- Heat to seperate double-strand to produce single strands
- Add probe that will hybridise to DNA sample
- By complementary base pairing
- Use autoradiography/UV light to view if probe is bond
2
Q
How many stages to genetic fingerprinting/screening
A
6
3
Q
What determines how long/large DNA fragments produced are
A
Greater number of VNTRs = larger fragment
4
Q
How does fragment size influence distance travelled by gel electrophoresis
A
Smaller fragements move further
5
Q
In what direction do DNA fragments move
A
From negative to positive electrode
6
Q
Why do DNA fragments move in the direction that they do
A
DNA Fragments are negatively charge, so move towards positive electrode
7
Q
What forms the bulk of a gel electrophoresis machine
A
Agarose gel
8
Q
How to visualise results from gel electrophoresis
A
- Add nylon filter to gel
- Heat to seperate-strand, to produce single strands
- Add probe that will hybridise to DNA sample
- By complementary base pairing
- Use autoradiography/UV light to view is probe bound
