## Did you know that...

...DNA analysis methods are an everyday part of diagnostics in modern society. We could already see this during the pandemic COVID-19. After the global spread of the SARS Cov2 virus, it was necessary to quickly and efficiently track down people who were carriers of the virus to isolate them and prevent further spread. Since symptoms of illness are not sufficient evidence of the presence of the virus in the body (other diseases have similar symptoms), more sophisticated diagnostic methods had to be used. Nucleic acid and its primary sequence of nucleotides are characteristic of a particular organism and also of a virus, so methods aimed at identifying a section of nucleic acid can detect the presence of specific virus with high accuracy. In addition to accuracy, the speed of detection is also important in the case of a spreading infection. The PCR reaction, the result of which can be evaluated within 1 to 2 hours, is a tremendous advantage over long-term cultivation of cells. Thus, RT-PCR immediately became the predominant method in the diagnosis of COVID -19. The Sars Cov2 virus has its genetic information stored in an RNA molecule on which no PCR reaction can be performed, so it must first be transcribed into DNA in a process of reverse transcription. This step is a standard part of the RT-PCR reaction. As you have learned in this chapter, the RT-PCR method allows us to determine the amount of input nucleic acid in the reaction, so it also gives us very valuable information when diagnosing the virus. Individuals with a higher amount of virus in their body may be more contagious and therefore pose a greater risk to those around them.