Duke researchers recently mapped the evolutionary turning point that transformed the pathogenic Cryptococcus fungus from an organism with thousands of sexes to only two. They found that during evolution, a reshuffling of DNA known as translocation brought together separate chunks of sex-determining genes onto a single chromosome, essentially mimicking the human X or Y chromosome. Surprisingly, these translocations occurred at the chromosome’s centromeres, regions so dense that they were once thought to suppress recombination. http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.2002527