3.8.4.3- Genetic fingerprinting Flashcards
Uses of genetic fingerprinting- (3)
- forensic science
- medical diagnosis
- ensure animals/plants aren’t closely related before breeding
Genetic fingerprinting- 7) Analysis (1+3)
Position of DNA bands are compared to
1 ) identify genetic relationships
2) identify presences of disease-causing- gene
3) Match unknown samples from crime scene
Genetic fingerprinting- 6) Development (3)
1) Agar gel will SHRINK & CRACK as it dries
2) VNTR & DNA probes are transferred to a nylon sheet
3) Nylon sheet exposed to x-rays (if r) or UV light (if f)
Genetic fingerprinting- 5) Hybridisation (2)
1) Mix DNA probes (C in base sequence to VNTRs) with single stranded DNA VNTRs on agar gel
2) They will hybridise (join together)
Genetic fingerprinting- 4) Separation (5)
1) DNA samples loaded into small wells in agar gel
2) gel placed in buffer liquid with an electric voltage applied
3) DNA is - charged, so DNA samples move through gel toward + end of gel
4) Agar gel creates RESISTANCE for moving DNA & smaller pieces move FASTER & FURTHER along gel; so different length of VNTRs are separated
5) An alkaline added to separate the double strands of DNA
Genetic fingerprinting- 3) digestion (2)
1) Restriction endonucleases added, to cut DNA> smaller fragments
2) Enzymes added which cut close to target VNTRs
Genetic fingerprinting- 1&2) collection & extraction (2)
1) small sample of DNA collected
2) If sample of DNA is small, then PCR used to AMPLIFY amount of DNA
Stages of genetic fingerprinting (7)
1) collection
2) Extraction
3) Digestion
4) Separation
5) Hybridisation
6) Development
7) Analysis
What is genetic fingerprinting?
analysis of VNTR DNA fragments to determine genetic relationships & genetic variability within a population
what are VNTRs
=Variable Tangdem Repeats
=introns in 95% of DNA consists of many VNTRS
