After performming four PCR experiments you run a gel to dete

After performming four PCR experiments, you run a gel to determin if your product was correctly made. You are looking for a band that is about 460 base pairs. Give an explanation as to the appearance of the 789 base pair band in the experiement for lane 2. Give one solution to correcting this problem.

Solution

Answer:

The most probable reasons for the appearance of a 789 bp band in the PCR might be the longer extension time or incorrect annealing temperature used during the PCR cycles.

A probable solution to this problem is reducing the extension time to 30 seconds such that ony the 460bp fragment gets amplified (Taq has an extension rate of 1000bp/minute). Another solution is changing the annealing temperature to reduce non specific binding of the primers. This can be achieved efficiently by running a gradient PCR.