Nucleic Acid Amplification

Molecular biology techniques allow the exponential duplication of small amounts of plant nucleotide fragments (RNA or DNA sequences), to create more sample. The most well-known method is the polymerase chain reaction (PCR) which uses a thermostable DNA polymerase enzyme to assemble nucleotides (deoxynucleotide triphosphates (dNTPs)) into a new DNA strand, using single-stranded DNA as a template and DNA oligonucleotides (DNA primers) to initiate DNA synthesis. Thermal cycling physically separates the two DNA strands in the double helix (DNA melting), then each strand serves as a template for further synthesis. Transcription mediated amplification (TMA) and Hot-start PCR are modifications of traditional PCR. In reverse transcriptase PCR (RT-PCR) a reverse transcriptase first converts the RNA strand template into DNA, then PCR is carried out to amplify the DNA template. The ligase chain reaction (LCR) method amplifies the probe nucleic acid instead, and can be more specific.