Scientists have discovered genetic factors in bats that shed light on their immune responses.
Five years after the COVID-19 pandemic began, researchers worldwide continue to investigate its impact and seek new strategies to prevent similar outbreaks in the future. A team of international scientists has potentially uncovered a vital clue in this effort, with significant contributions from a lab at Texas Tech University.
Led by David Ray, a professor and associate chair in the Department of Biological Sciences, the Ray Laboratory participated in a study on bat genomes published in the journal Nature. This research identified genetic elements in a specific bat species noted for more immune system adaptations compared to other animals.
The findings indicate that a gene prevalent in certain bats could lower the production of the SARS-CoV-2 virus by as much as 90%, paving the way for innovative medical treatments against viral infections.
“Bats possess a remarkable capacity to fend off some of the most severe effects of viral infections, which can leave us quite ill,” Ray stated. “While we may struggle significantly, bats show minimal reactions when they encounter the same pathogens.”
Ray explained that his lab contributed to the annotation of bat genome assemblies. Genome annotation involves detailing all aspects of the genome — including genes, regulatory sequences, and both coding and non-coding areas. The Texas Tech laboratory pinpointed the regions of transposable elements (TEs) within these assemblies, where portions of DNA can replicate themselves and induce variations in the genome.
Bats exhibit a distinctive repertoire of TEs among mammals, offering a potentially powerful mechanism for developing new genetic defenses against pathogens like coronaviruses.
“If every member of a species were genetically identical, they would all face the same infection risk — a single loss would mean total loss for the group,” Ray explained. “TEs facilitate genetic diversity within a species, enabling some individuals to thrive under environmental stressors like viral infections.”
This research is part of a larger global initiative called Bat1K, aimed at sequencing and assembling the genomes of all existing bat species, which total around 1,500, according to Ray. This project is led by the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany.
Michael Hiller, a professor of comparative genomics at Goethe University and key researcher at the Senckenberg Institute, is one of the principal investigators in the study. Both he and Ray serve on the executive board for the Bat1K consortium, and their collaboration offers a great opportunity for Ray’s lab to work with the global scientific community.
The lab focuses on studying genomes and their evolution, particularly regarding TEs. Past research has involved genomes from bats, other mammals, crocodiles, and various insects. The lab has collaborated with organizations such as the National Science Foundation, the U.S. Department of Agriculture, the state of Texas, and the Texas Department of Wildlife and Fisheries.
In this study, researchers specifically examined the ISG15 gene, which is linked to more severe cases of COVID-19 in humans. While bats carry many viruses, including those that can infect humans, they do not exhibit any disease symptoms when infected.
The research indicated that the ISG15 gene from bats can decrease SARS CoV-2 virus production by 80-90%. In contrast, the human ISG15 gene showed no antiviral effects during this study.
“Therefore, the ISG15 gene is likely among several components that assist bats in resisting viral diseases,” Hiller remarked. “These promising findings can serve as a foundation for further studies intended to unravel the unique adaptations of the bats’ immune system.”
