Dr. Magwene is a yeast geneticist whose work uses both wet lab and computational approaches. He is also the director of the Computational Biology and Bioinformatics Ph.D. program at Duke.

Dr. Magwene received his Ph.D. from the University of Chicago, and postdoctoral training at Yale and the University of Pennsylvania. He joined the faculty at Duke in 2004.

The yeast Cryptococcus deneoformans is a human pathogen that mainly lives in soil. It enters the body through the lungs and in immunocompromised individuals can spread to the brain. It is one of the most common causes of death in individuals with AIDS in sub-Saharan Africa, with one estimate that 70% of patients who become infected will die within 3 months.

Cryptococcus, like many yeasts, can reproduce both sexually and asexually. Asexual reproduction produces genetically identical daughter cells, whereas sexual reproduction involves combining genetic information from both parents, producing daughter cells that have novel combinations of genes. Thus, sexual reproduction is a source of variation that can lead to the evolution of more aggressive strains. However, it is not well understood how much genetic recombining happens in each mating and if there are particular regions of the genome that are more or less likely to be recombined.

In a recent paper, Dr. Magwene and colleagues looked at those two questions. In particular, they were interested in the fact that Cryptococcus have two “sexes” (mating type a and mating type α) and can sexually reproduce bisexually (a x α) or unisexually (α x α). They found that the α x α mating had a lower frequency of genetic recombination events compared to the a x α mating. They also generated a list of “hot spots” where recombination events were more likely to occur and showed that this was related to the DNA sequence in those regions.

Together, these results provide new information about how the genome of this pathogenic yeast is evolving. This will be useful in making predictions about how quickly it will become more virulent and which genetic regions are likely to be involved.