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The understanding of the epidemiology and pathogenic features for Cryptococcus neoformans infections can now be aided by the use of molecular biological techniques. In the last three decades, model systems for eukaryotic molecular biology have developed around certain fungi, such as Saccharomyces cerevisiae, Schizosaccharomyces pombe, Neurospora crassa, and Aspergillus nidulans. In the late 1980s, studies for the present foundation of molecular biology in C. neoformans began. The early development of molecular biological techniques for studying a pathogen generally involves questions of epidemiology in relationship to pathogenicity. In fact, little work has yet been performed on the genetics and molecular biology of mitochondrial DNA in C. neoformans. The use of polymerase chain reaction (PCR) technology combined with repetitive primers (arbitrary primed PCR) has allowed investigators to identify the DNA fingerprints of different fungal strains rapidly, specifically, and with a minimal number of DNA purifications. Recent work in molecular phylogeny of C. neoformans has focused on other genes and their ancestral lineages. Investigations into C. neoformans gene structures and the understanding of gene regulation in this yeast are in their infancy.
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