Bat gene clue to beating bugs- Research

SINGAPORE – Bats harbour viruses that can infect and even kill humans and animals, like Sars, Hendra and Nipah. Yet infected bats rarely fall sick.

Now, a Singapore-led team of international scientists has worked out a possible reason and believes it could help stop viruses leaping to humans and other animals.

The findings could even help to treat viral illnesses.

The key lies in bat genes. In July, the researchers started sequencing the genomes – the whole set of genes – of two very different bats.

One was a large fruit bat, a member of a group called megachiroptera. The other was a small insect-eating one belonging to a group called microchiroptera.

As these species are so different, any genes they share come from the last common ancestor of both bats.

Professor Wang Linfa, director of the Duke-NUS graduate medical school’s Emerging Infectious Diseases Programme, led the team, which studied which genes had been selected most successfully during evolution.

Bats are the only flying mammals, and flight takes a great deal of their energy. The higher metabolic rates that supply this energy also produce toxic by-products that damage DNA. But bats seem to have evolved ways to protect their cells against this damage, Prof Wang explained. These DNA-repair genes also play a role in immune pathways, so researchers think they may help to protect bats.

A group of genes involved in inflammation was completely absent in bats. Inflammation is the body’s response to an invader, such as a virus, resulting in viral illness.

Said Prof Wang: “We don’t want to jump to conclusions that this means bats have less inflammation during viral infection. It’s only one discovery and we have to do more to functionally prove that it contributes to less pathology in viral infection in bats.”

But simply responding less to viruses could be part of why bats do not fall ill, he said.

Prof Wang led an international team spanning Singapore, China, Denmark and the US. Its work, published yesterday in the journal Science, may one day help prevent transmission of these viruses. It may point to better ways to treat viral diseases by using gene therapy, for example, to control inflammation, Prof Wang said.

National University of Singapore evolutionary biologist Rudolf Meier, who was not involved in the study, said some changes in the bat genes were present in other species, including humans, but without the protective DNA-repair or immune-system effects. He said the results were not wrong, but not conclusive.

Source: The Straits Times

Category: Education