Duke University Medical Center researchers have said that the pathogenic fungi self protect them during sexual reproduction and stop unwanted genetic mutations. The mutation risks occur during their mating. The fungal genome creates a gene-silencing pathway for protection.

This pathway was discovered in Cryptococcus neoformans, a fungus that is responsible for causing over one million cases of lung and brain infection cases in humans each year, and more than 600,000 deaths.

A related species, Cryptococcus gattii, is already causing an outbreak in the Pacific Northwest raising public health concern."This discovery of how the genome is protected during sex might be leveraged as an Achilles' heel in the battle against C. neoformans, which frequently causes life-threatening illness in people," said senior author Joseph Heitman, M.D., Ph.D., chair of the Duke Department of Molecular Genetics and Microbiology.

"This protective silencing effect also operates in some animals, and our studies demonstrate that the pathway operates to defend the genome during sexual reproduction."

Fungi produce airborne spores during sexual reproduction which are inhaled into the human lungs and are thought to be the source of many infections.

C. neoformans’s defense mechanism is a sex-induced RNAi (RNA interference) that protects by "silencing" the DNA, so that it is not vulnerable to mutations.

Published by Medicaldaily.com