Study uncovers recurrent chimeric transcripts in COVID-19 patients with severe infections

A new study published in the journal Viruses by Open Access MDPI Journals has detailed some of the molecular functions behind the development of severe COVID-19 cases, finding novel chimeric transcripts that fuse to form hybrid genes, which can lead to severe infections.

The study, by researchers Milana Frenkel-Morgenstern of Bar-Ilan University, Sumit Mukherjee, Rajesh Detroja and Sunanda Biswas Mukherjee, analyzed "several publicly available blood transcriptome datasets" of severe and mild COVID-19 patients, as well as others with severe viral respiratory infections, as well as healthy individuals. The researchers found there were 424 severe COVID-19-specific chimeric transcripts, 42 of which were recurrent, the study stated. 

Chimeric transcripts are produced when different genes are fused together to form a hybrid gene. Hybrid genes can promote functional alterations of the cell, which could be linked to the development of disease severity, the report read.

Further analysis revealed that 189 chimeric transcripts were common to severe COVID-19 and multiple severe respiratory viral infections. Pathway and gene enrichment analysis of the parental genes of these two subsets of chimeric transcripts suggests that they are potentially involved in immune-related processes, interferon signaling, and inflammatory responses, which could be associated with immune dysfunction, leading to the development of disease severity.

"This study is the first to provide a detailed expression landscape of chimeric transcripts in severe COVID-19 and other severe respiratory viral infections," the authors said. "The findings could help researchers better understand the molecular mechanisms underlying disease severity and develop new therapeutic strategies to combat COVID-19."  

In addition, "this study successfully uncovered the hidden layers of the blood transcriptome from the various respiratory viral infected patients and identified several potential functionally relevant chimeric transcripts unique to severe COVID-19," the authors wrote.

The study authors added that "further experimental studies are necessary to elucidate the specific functions of these chimeric transcripts" in COVID-19 and other infectious diseases.