Comparison of in-house SARS-CoV-2 genome extraction procedures. A need for COVID-19 pandemic

Abstract

Among the methods used to diagnose COVID-19, those based on genomic detection by q(RT)-PCR are the most sensitive. To perform these assays, a previous genome extraction of the sample is required. The dramatic increase in the number of SARS-CoV-2 detection assays has increased the demand for extraction reagents hindering the supply of commercial reagents. Homemade reagents and procedures could be an alternative. Methods: Nasopharyngeal samples were extracted by seven different methods as well as the automatic method MagNaPure96, to detect SARS-CoV-2. Results: All protocols show sensitivity higher than 87%, in comparison with reference method, for detecting SARS-CoV-2 as well as human βglobin. Conclusions: Our results support that these procedures, using common and cheap reagents, are effective to extract RNA (from SARS-CoV-2) or DNA (from human βglobin) genome from nasopharyngeal swabs. Furthermore, these procedures could be easily adopted by routine diagnostic laboratories to implement detection methods to help to fight against COVID-19 pandemic.

Extraction Bottleneck in the Diagnosis of SARS-CoV-2: Evaluation of an Alternative Protocol Derived from Veterinary Use

“…Although they provided relatively rapid results (average 3–4 h), several problems emerged in clinic diagnostics, particularly in RNA isolation from clinical samples [ 9 ]. This step is pivotal since both quality and quantity of the genome obtained could affect the subsequent amplification process [ 10 ]. RNA isolation procedures typically involve three general steps: cell lysis, separation of RNA from other macromolecules such as DNA, proteins and lipids and the following RNA concentration; however, it was a procedure that wasted time and resources [ 11 ].…”