Which of the following sets of primers could be used to PCRa

Which of the following set(s) of primers could be used to PCR-amplify the target DNA sequence shown in boldface? For each set of primers, explain why they would or would not amplify the target DNA. 5\'-GGCTAAGATCTGAATTTTCCGAGGAGATATCCGCTAATTGGGCAATAATGTAGCGCCTT-3\' a) 5\'-GGAAAATTCAGATCTTAG-3\'; 5\'-TGGGCAATAATGTAGCG-3\' b) 5\'-GCTAAGATCTGAATTTTC-3\'; 5\'-CGCTACATTATTGCCCA-3\' c) 5\'-CGGAAATTCAGATCTTAG-3\'; 5\'-CGCTACATTATTGCCCA-3\' d) 5\'-GCTAAGATCTGAATTTTC-3\'; 5\'-TGGGCAATAATGTAGCG-3\'

Solution

Answer is a. In a thestatement set, of primers amplify the target DNA. Because, in a, the first primer is Complimentary to 5\' side sequence of the target (bold) sequence. If we want to amplify a DNA, we need to design primers to that sequence which is in upstream and downstream to the target DNA. In option a, the 3\' side of first primer show complementary to upstream side of target DNA