Lab Canada

BC scientists lead mapping of killer fungus genome

Vancouver, BC – Scientists say they are a step closer to developing drug targets to treat fungal meningitis – the infection linked to at least three deaths on Vancouver Island – thanks to the sequencing of two Cryptococcus genomes by an international team that included researchers at the University of British Columbia and the BC Cancer Agency’s Michael Smith Genome Sciences Centre in Vancouver.

"This fundamental information will help develop better diagnostic tools, as well as antifungal drugs and potential vaccines," says Prof Jim Kronstad of the Michael Smith Laboratories at UBC. "

Dr Kronstad, a microbiologist, initiated the mapping portion of the study in collaboration with scientists at the BC Cancer Agency’s Michael Smith Genome Sciences Centre, and co-ordinated efforts with the international team, including scientists from the Institute of Genomic Research, Stanford University and Duke University in the US. The team published its findings last week in Science.

In a three-year investigation, researchers sequenced two genomes for the Cryptococcus group of fungal pathogens. The team is currently completing and analyzing a third genome, Cryptococcus neoformans gatti, the species that caused the deadly outbreak of infections which were first detected on Vancouver Island in 1999. They will make comparisons between the genomes through a partnership with the UBC Bioinformatics Centre and publish the sequence of the additional genome this year.

Cryptococcus is a yeast-like fungal organism that can cause life-threatening infections, the most common being fungal meningitis that affects about 10% of AIDS patients in North America and 30% of patients in Africa.

Fungal meningitis generally attacks those with weakened immune systems. Individuals can become infected by inhaling Cryptococcus spores found in soil contaminated with decaying pigeon droppings. Symptoms of meningitis include severe headache, stiff neck, fever and vomiting. The disease can be fatal if not treated with anti-fungal drugs.

Support for this research was provided the Natural Sciences and Energy Research Council (NSERC) and by the National Institutes of Health in the US. The current Cryptococcus genome sequencing project underway in Vancouver is funded by Genome Canada and Genome BC.