bioRxiv: Study Found the Global SARS-CoV-2 Is Composed of Six Main Subtypes

The World Health Organization announced the global pandemic of COVID-19 in March 2020, the second pandemic in the 21st century. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an RNA beta coronavirus of the Coronaviridae family. The expansion of virus populations, such as SARS-CoV-2, has accumulated many shared polymorphisms, which has caused confusion in traditional clustering methods. In this case, a method to reduce the complexity of the sequence space occupied by the SARS-CoV-2 population is necessary for accurate clustering.

Recently, researchers from the Federal University of Ubrantia, the Federal University of Visosa, and the University of Brasilia, Brazil, proposed to subdivide the global SARS-CoV-2 population into 16 well-defined subtypes by focusing on polymorphisms in widely shared nonstructural cistrons (nsp3, nsp4, nsp6, nsp12, nsp13, and nsp14), structural genes (spike proteins and nucleocapsid), and accessory genes (ORF8). The related research results were published on the preprint server bioRxiv, and the article title is “The global population of SARS-CoV-2 is composed of six major subtypes”.

The researchers found that the six virus subtypes dominate the patient population, but all 16 subtypes of viruses exhibit amino acid substitutions that may have phenotypic significance. The researchers speculate that the virus subtypes detected in this study are records of the early stages of SARS-CoV-2 diversification. These viruses are randomly sampled to form virus populations around the world, which is a typical founder effect.

The researchers said that the genetic structure of the virus identified by SARS-CoV-2 infected persons provides substantial guidance for maximizing the effectiveness of candidate vaccines or drug trials.