Bengaluru: a team from the Indian Institute of Sciences (IISc) has reported a new technique for virus detection that could help overcome the limitations and challenges of real-time reverse transcription polymerase chain reaction (RT-PCR).
RT-PCR it is the standard test used to detect viruses such as Ebola and SARS-CoV-2. A throat swab or blood sample may have only a few samples of viral DNA or RNA molecules, making it difficult to detect the virus.
“Therefore, the DNA number or RNA molecules is amplified by PCR. This newly generated DNA is labeled by fluorescent molecules and monitored in real time to estimate the level of DNA (or viral RNA) in the sample. This technique also uses a temperature-regulating thermocycler because different temperatures are required in each amplification step of DNA or RNA molecules. However, the use of thermal cyclers and real-time monitoring limits the use of RT-PCR in areas with scarce resources”, according to IISc.
the new method
To overcome this limitation, Priyanka Valloy and Rahul Roy from the department of chemical engineering, IISc, used an alternative method called ‘Recombinase Polymerase Amplification’ (RPA) in which all reactions take place near room temperature. “By developing a mathematical model of RPA kinetics that estimates the amount of initial DNA as a function of the amount of genetic material present at the endpoint, they developed a new method called ‘quantitative endpoint RPA (qeRPA)’ that eliminates the need analysis in real time. monitoring,” added IISc.
The researchers then used qeRPA to determine the initial number of DNA copies in blood samples from dengue patients. “The results of qeRPA were consistent with those obtained from qRT-PCR and were faster and easier to implement. The team hopes that this method can be used to detect nucleic acids such as DNA or RNA in diagnostic centers in resource-constrained areas such as remote villages,” said IISc.
