Answer to Question #124818 in Biology for Sreelakshmi

Question

Polymerase chain reaction (PCR) is a revolutionary method invented by Kary Mullis in the 1980s which copies the target sequence defined by a pair of primers exponentially. Can exponential amplification of any random sequence of DNA be achieved in PCR with only single primer? Hint: Refer the schematic in the diagram that represents randomly amplified polymorphic DNA (RAPD) marker technology. You can substantiate your answer with help of this diagram, if required.

Answer 1

It is possible to perform the polymerase chain reaction using only a single primer. During each cycle of amplification, the primer will anneal to the same strand producing complement DNA strand. As a result, one primer can be used to amplify a certain single-stranded DNA. However, the amount of produced DNA per cycle will be much lower than during the traditional PCR amplification. As a result, exponential amplification of any random sequence of DNA cannot be achieved in PCR with only a single primer.