CLONAL EXPANSION OF THE PSEUDOGYMNOASCUS DESTRUCTANS GENOTYPE IN NORTH AMERICA IS ACCOMPANIED BY SIGNIFICANT VARIATION IN PHENOTYPIC EXPRESSION

Abstract

White-nose syndrome is an emerging infectious disease that first appeared in 2006. Since its emergence, it has caused over 5.5 million deaths of bats in North America. Pseudogymnoascus destructans, a psychrophilic fungus, is the causative agent of white-nose syndrome. White-nose syndrome is characterized by the growth of P. destructans on the nose, wings, and/or ears of the bat causing epidermal erosions and ulcers. Previous studies determined that the population of P. destructans in North America is clonal. However, no Canadian isolates of P. destructans were used. In this study, multilocus sequence typing and DNA fingerprinting was used to genotype 112 North American isolates. My results showed that the population in Canada had the same genotype as those from the US and there was also evidence of minor genetic variation in three Canadian isolates. Using 16 P. destructans isolates representative of various geographical locations in North America, significant phenotypic variations based on mycelial growth, production of exudates, and production of pigments and diffusion into agar media were observed. Overall, my results indicate a clonal genotype expansion of P. destructans throughout North America that is accompanied by significant phenotypic variation.