A student is running gels to sequence a DNA fragment as below. In addition to running four
sequencing reactions with the requisite ddNTPs, they also include four 'mystery' reactions
representing variants of the first sequencing lane (using ddATP to sequence T in the template) in
which one or more components of the reaction have been omitted or inappropriately added.
Sequenced ACGT
Template TGCA
Longer
Shorter
5' AGATAGCGCTAGCGATACCGAGG 3'
3' TCTATCGCGATCGCTATGGCTCC 5'
Full length
Unextended primer
Q2.1
1 Point
What was inappropriately added/omitted in mystery lane 3?