Chitra GeneLAMP-N for Covid-19 Test

• 17 Apr 2020

Why in News

• Sree Chitra Tirunal Institute for Medical Sciences and Technology (SCTIMST), Trivandrum (Kerala), has developed a diagnostic test kit that can confirm Covid-19 in 2 hours at low cost.
  
  • SCTIMST is an Institute of National Importance under the Department of Science and Technology (DST).

Key Points

• The test kit, funded by the DST called Chitra GeneLAMP-N, is highly specific for SARS-CoV-2 N-gene and can detect two regions of the gene.
  
  • This would ensure that the test does not fail even if one region of the viral gene undergoes mutation during its current spread.
• It is a confirmatory diagnostic test, which detects the N Gene of SARS- COV2 using reverse transcriptase loop-mediated amplification of viral nucleic acid (RT-LAMP).
• The results can be read from the machine from the change in fluorescence.
  
  • Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
• The tests performed at National Institute of Virology (NIV), Alappuzha (Kerala) (authorized by Indian Council of Medical Research (ICMR)) show that Chitra GeneLAMP- N has 100% accuracy and match with test results using Reverse Transcription Polymerase Chain Reaction (RT-PCR).
• This has been intimated to Indian Council of Medical Research (ICMR), the authority to approve it, for Covid-19 testing in India, following which License needs to be obtained from Central Drugs Standard Control Organisation (CDSCO) for manufacture.
• Advantages
  
  • A total of 30 samples can be tested in a single batch in a single machine allowing a large number of samples to be tested each day.
  • Current Polymerase Chain Reaction (PCR) kits in India enable detection of E gene for screening and RdRp gene for confirmation. Chitra GeneLAMP-N gene testing will allow confirmation in one test without the need for a screening test and at much lower costs (less than Rs. 1000/test).
  • Chitra GeneLAMP-N makes confirmatory tests results of Covid-19 possible in 2 hours.
    
    • The detection time is 10 minutes, and the sample to result time (from RNA extraction in swab to RT-LAMP detection time) will be less than 2 hours.
  • The testing facility can be easily set up even in the laboratories of district hospitals with limited facilities and trained laboratory technicians.

Gene

• Gene, unit of hereditary information.
• Genes achieve their effects by directing the synthesis of proteins.
• Genes are composed of Deoxyribonucleic acid (DNA), except in some viruses, which have genes consisting of a closely related compound called Ribonucleic acid (RNA).

Reverse Transcription-based Loop Mediated Isothermal Amplification (RT-LAMP)

• It is a simple quantitative detection method.
• In this method, a DNA copy of the viral RNA is generated by reverse transcriptase, and then isothermal amplification is carried out to increase the amount of total DNA.
  
  • A reverse transcriptase (RT) is an enzyme used to generate complementary DNA (DNA) from an RNA template, a process termed reverse transcription.
  • Isothermal amplification enables rapid and specific amplification of DNA at constant temperature (60-65 °C).

Source : PIB