Same-Sex Mating in Cryptococcus?

Since Cryptococcus, like most club fungi (Basidiomycota), must mate to produce airborne spores, researchers have been faced with a mystery. "The unusual thing about C. neoformans and C. gattii is for the vast majority of the world you can only find [one sex]," says molecular geneticist James Fraser of the University of Queensland. The trouble is that, without mating, the yeast reproduces clonally, and individual cells typically are not tiny enough to infiltrate the lungs. So how can only a single sex of Cryptococcus infect people in the open air?