Frog's immune system is key in fight against killer virus

Feb 27, 2009

(PhysOrg.com) -- Scientists from Queen Mary, University of London have discovered how changes to a frog's immune system may be the key to beating a viral infection which is devastating frog populations across the UK.

Communities of common frogs (Rana temporaria) are being struck down by a foreign virus which is estimated to be killing tens of thousands of frogs in the UK each year. When it strikes garden ponds, the surrounding lawn becomes strewn with dead frogs, some with skin ulcers so severe they reduce limbs to stumps, others with internal bleeding. The virus, called Ranavirus, has invaded the home counties around London, and is now spreading north and west.

Writing in the journal PLoS One, Dr Amber Teacher describes how the frogs' immune system has responded to the virus. Working with her fellow scientists at Queen Mary, University of London and experts at the Institute of Zoology, she studied ponds where Ranavirus deaths are occurring year after year, and consistently found changes to a gene called the MHC, which codes for a major part of the frog's immune system.

Dr Teacher explains: "It seems, as Darwin would have predicted, that the plucky surviving frogs have passed on to their descendants an immune system which is better tuned to the new threat."

Teacher also found that the frogs' immune systems are simpler than many other animals, including humans, who have several MHC genes doing a similar job. She adds: "This discovery has helped identify the point in our evolutionary history when this multiplication of genes occurred. With luck, even the frog's simpler system will be sufficient to win their battle".

It is too early to determine if the adaptation in the frogs' immune response will be enough to save them from the virus. Her colleague Professor Richard Nichols, from Queen Mary's School of Biological and Chemical Sciences added: "From a scientific point of view we could learn as much about the fight against viruses, whether the frogs succumb or they don't; but from a personal point of view I hope these changes are the first signs that the frogs getting the upper hand over the virus."

More information: ‘Evidence for Directional Selection at a Novel Major Histocompatibility Class I Marker in Wild Common Frogs (Rana temporaria) Exposed to a Viral Pathogen’ will be published online in PLoS ONE on Wednesday, 25 February.

Source: Queen Mary, University of London

Explore further: Breakthrough in coccidiosis research

add to favorites email to friend print save as pdf

Related Stories

Stinky frogs are a treasure trove of antibiotic substances

Nov 30, 2011

Some of the nastiest smelling creatures on Earth have skin that produces the greatest known variety of anti-bacterial substances that hold promise for becoming new weapons in the battle against antibiotic-resistant ...

Humans, sharks share immune-system feature

Sep 30, 2011

A central element of the immune system has remained constant through more than 400 million years of evolution, according to new research at National Jewish Health. In the September 29, 2011, online version ...

Gene removal could have implications beyond plant science

Apr 16, 2014

(Phys.org) —For thousands of years humans have been tinkering with plant genetics, even when they didn't realize that is what they were doing, in an effort to make stronger, healthier crops that endured climates better, ...

Fighting antibiotic resistance with 'molecular drill bits'

Mar 17, 2014

In response to drug-resistant "superbugs" that send millions of people to hospitals around the world, scientists are building tiny, "molecular drill bits" that kill bacteria by bursting through their protective cell walls. ...

Recommended for you

Breakthrough in coccidiosis research

2 hours ago

Biological researchers at the Royal Veterinary College (RVC) are a step closer to finding a new cost-effective vaccine for the intestinal disease, coccidiosis, which can have devastating effects on poultry ...

Vietnam's taste for cat leaves pets in peril

6 hours ago

The enduring popularity of "little tiger" as a snack to accompany a beer in Vietnam means that cat owners live in constant fear of animal snatchers, despite an official ban.

New species of mayfly discovered in India

8 hours ago

Scientists have discovered a new species of mayfly in the southern Western Ghats, a mountain range along the west coast of India. In fact, this is the first time that any mayfly belonging to the genus Labiobaetis has be ...

User comments : 0