Tuesday, May 24, 2011

Is a mutated fungus killing American bats? - 24th May 2011

A fungus blamed for killing more than a million bats in the US since 2006 has been found to differ only slightly from an apparently harmless European version. The minor genetic differences could hold the key to preventing future deaths.

Alternatively, European bats may have been exposed to the virus longer and evolved resistance.

Jeffrey Foster at Northern Arizona University in Flagstaff, and colleagues, compared the genomes of strains of Geomyces destructans infecting US and European bats and found that the strain thought to cause lethal "white nose syndrome" (WNS) in the US is almost identical to one that is harmless to bats in Europe.

"There were very few mutational differences between the North American and European samples, strongly suggesting they're related," says Foster. The team presented their preliminary results last week at a conference in Little Rock, Arkansas.

If it is the DNA differences making the US version of the fungus virulent, then finding a treatment will be easier than if the reason for the transatlantic difference is that European bats have evolved resistance, says Foster.

The answer should come from Craig Willis at the University of Winnipeg in Manitoba, Canada, who is currently testing both strains on little brown bats from the US, to see if both versions cause WNS.

Irrespective of whether it is the nature of the fungus or evolved resistance, researchers in Europe told the meeting that they are trying to find out why European bats are not getting sick. "We've been taking wing-punch samples in the field for analysis to see if there are clues to survival in the genetics," says Natália Martínková of the Institute of Vertebrate Biology in Brno, the Czech Republic. Source