PCR Test

The polymerase chain reaction process forms the basis for the tests currently being used to assess SARS CoV 2 infection among the masses.

Polymerase Chain Reaction

The PCR is used to create multiple copies of a DNA. It uses the enzyme polymerase to create the copies exponentially using a chain reaction process. The PCR technique was invented by American biochemist Kary Mullis, who received the Nobel Prize for Chemistry in 1993 for it.

The PCR Test for SARS CoV 2

Since the SARS CoV 2 is an RNA virus, its genetic material is first converted into DNA using a process called reverse transcription, using the reverse transcriptase enzyme.  It is then subject to the PCR process to create copies. Probes (fluorescent DNA binding dyes) are used to detect the virus’ presence.

Time Taken

The time taken for completing the PCR test has been reduced from the previous case of 6 hours to current 4.5 hours. However, the addition of time taken for the sample collection and delivery, increases the time to about 24 hours.

Testing in India

India is making use of a two-stage testing to detect cases of COVID-19. The first stage is used to detect genetic components of common coronaviruses that affect humans. The second stage is to detect genes specific to SARS CoV 2. Currently, all labs have expanded their capabilities to perform both the stages of the test.