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Same-sex action helps thrush yeast thrive

Candida albicans cells can reproduce homosexually, which could help explain how the yeast develops resistance to treatment

A YEAST responsible for thrush can reproduce homosexually – potentially explaining ways it develops resistance to treatment.

When Candida albicans cells reproduce by mating, they have two sex types, “a� and “alpha�. Richard Bennett of Brown University in Providence, Rhode Island, and his colleagues mixed the two types and saw matings between same-sex cells, but only a few (Nature, ).

They saw many more when they boosted a pheromone secreted by “a� cells that draws same-sex cells together. They did this by disabling an enzyme in “a� cells that usually destroys the “same-sex� pheromone.

Now they want to find out what could make this happen in nature, such as changes in acidity in the mouth, gut or vagina.

In 1999, a lethal strain of a related yeast, Cryptococcus neoformans, emerged on Vancouver Island in British Columbia, Canada, through same-sex mating. “The findings suggest that unisex mating may be linked to virulence,� says of Duke University in Durham, North Carolina.