What is touchdown PCR and why it is performed?

It is a method for increasing specificity of PCR reactions. Touchdown PCR uses a cycling program where the annealing temperature is gradually reduced (e.g. 1-2°C /every second cycle). The initial annealing temperature should be several degrees above the estimated Tm of the primers.

What is touch up PCR?

Touch up PCR is a method of amplifying a PCR-product that have bad primers or are troublesome in other ways. This is an example: 98°C for 2:00 – Denaturing and warm up. 98°C for 0:10 – Denaturing after each cycle.

What is nested PCR used for?

The purpose of nested PCR is to increase assay sensitivity by re-amplifying the target from a template previously enriched by the first PCR.

What is the purpose of 50c step in PCR?

During this stage the reaction is cooled to 50-65⁰C. This enables the primers to attach to a specific location on the single-stranded template DNA by way of hydrogen bonding (the exact temperature depends on the melting temperature of the primers you are using).

What is the PCR technique?

Polymerase chain reaction (PCR) is a laboratory technique used to amplify DNA sequences. The temperature of the sample is repeatedly raised and lowered to help a DNA replication enzyme copy the target DNA sequence. The technique can produce a billion copies of the target sequence in just a few hours.

What is ARMS PCR?

The Amplification Refractory Mutation System PCR (ARMS-PCR) is one of the most accurate tools in genetic disease diagnosis in recent days. It is a gold standard method for thalassemia and sickle cell anemia. ARMS-PCR is used for genotyping SNP (single nucleotide polymorphism) with the help of refractory primers.

How long is a PCR cycle?

Most users of the polymerase chain reaction (PCR) would describe it as a fairly fast technique, taking about 45 min to an hour to complete 40 cycles, depending on the particular protocol and instrument used.

What is a primer in PCR?

A primer is a short, single-stranded DNA sequence used in the polymerase chain reaction (PCR) technique. In the PCR method, a pair of primers is used to hybridize with the sample DNA and define the region of the DNA that will be amplified. Primers are also referred to as oligonucleotides.