Molecular Diagnostics Flashcards
1
Q
What does it mean when a test has more specificity?
A
- the test is more specific/selective
- there will be less false positives
2
Q
What does it mean when a test has more sensitivity?
A
- the test is highly sensitive to everything
- will have more false positives
3
Q
Describe Electrophoresis
A
- identifies DNA/RNA/Protein by separation in electrophoretic field
- negative molecules move toward the positve end
- separation depends on how far the molecules move through the medium
- smaller molecules move faster
4
Q
Describe Restriction Fragment Length Polymorphism
A
- restriction enzymes specifically cut DNA
- the location of these cuts are known and specific to amino acid sequences
- run on a gel to determine how many cuts were made, and compare to a DNA sequence
5
Q
Describe Hybridization and Probe
A
- a labeled probe binds to a complementary single-stranded sequence
- high degree of specificity
6
Q
Describe Nuclear Acid Amplification
A
- enzyme-mediated process to synthesize copies of targeted nuclei acid
- high sensitivity
- PCR, LAMP
7
Q
What are the steps of PCR?
A
1) denaturation: heat briefly to separate DNA strands
2) annealing: cool to allow primers to form hydrogen bond with ends of target sequences
3) extension: DNA polymerase adds nucleotides to the 3’ end of each primer
8
Q
Describe PCR Primers
A
- random or specific
- length is based on annealing temp
- single-stranded DNA fragments, complementary to sequences that will be replicated
- distance between primer binding site determines the size of the product
9
Q
Describe Real-Time or Quantitative PCR
A
- probe or dye to generate fluorescent signal from the product
- signal in real time allows quantification of starting material
- signal: exponential curve with a lag phase, log phase, and stationary phase
- lag phase is inversely proportional to the amount of starting material
