Consider the following 45 base-pair (bp) DNA sequence:
1 10 20 30 40
| . | . | . | . | .
5’-CGCACCTGTGTTGATCACCTAGCCGATCCACGGTGGATCCAAGGC-3’
|||||||||||||||||||||||||||||||||||||||||||||
3’-GCGTGGACACAACTAGTGGATCGGCTAGGTGCCACCTAGGTTCCG-5’
You also have a collection of short DNA primers:
Primer 1: 5’-CGTGGA-3’
Primer 2: 5’-TGTGTT-3’
Primer 3: 5’-ATCCAA-3’
Primer 4: 5’-CCTTGG-3’
You put together several reaction mixtures, run them in the thermocycler under conditions that should produce a product if the reaction mixture is correct.
All mixtures contain:
The 45 bp DNA fragment
DNA polymerase that can function at high temperature
The necessary buffer conditions
For each mixture, indicate whether or not the PCR reaction would produce a product. If a product would be produced, give the length of that product in base-pairs (bp); if no product would be produced, give zero “0” for the length.
Reaction Added to Mixture Length of Resulting Product
1
dATP, dGTP, dCTP
Primer 2
Primer 4
unanswered
2
dATP, dGTP, dCTP, dTTP
Primer 2
unanswered
3
dATP, dGTP, dCTP, dTTP
Primer 2
Primer 4
unanswered
4
dATP, dGTP, dCTP, dTTP
Primer 1
Primer 3
unanswered
5
dATP, dGTP, dCTP, dTTP
Primer 2
Primer 3
1- ANS=0
2- ANS=0
3- ANS=38
4- ANS=0
5- ANS=0
Trippiest problem ever