Question

23. A PCR reaction is performed, and the negative control demonstrates the presence of a detectable number of PCR product (amplicons) by capillary electrophoresis. What is the most likely cause?

Answer 1

Answer:

Contamination of the control sample (negative control) with DNA

Explanation:

The Polymerase Chain Reaction (PCR) is a technique widely used in molecular biology laboratories to amplify a target DNA fragment using primer pairs and DNA polymerase. In PCR experiments, it is imperative to include both positive and negative controls. The positive control refers to the amplification of a PCR product (amplicon) of known molecular size during PCR reaction in order to ensure the correct molecular weight of the target DNA fragment. The negative control refers to the inclusion of a sample without DNA in order to ensure that no contamination with DNA has occurred in the other samples.