Cyanophages are viral parasites of cyanobacteria.  Marine cyanophages are thought to play a vital role in the biogeochemical cycle through what is called the viral shunt.  Freshwater cyanophages play a somewhat unclear role in the control and destruction of cyanobacterial blooms.  Both marine and freshwater phages, as well as all other types of bacteriophages, play an essential role in genetic biodiversity through transduction.  The movement of genetic information through transduction is called horizontal gene transfer (HGT).  Since cyanobacterial blooms can produce potent hepatotoxins and neurotoxins, there is interest in distinguishing and controlling toxic strains of cyanobacteria.  If toxin genes within toxic cyanobacteria could be disrupted by the introduction of an insertional sequence from a transducing phage in the middle of the toxin gene, then that might be a useful way of controlling toxic cyanobacterial blooms.  In this way, HGT could be leveraged to put evolutionary pressure on toxic cyanobacterial strains to delete the toxin gene.  The Dreher Lab is interested in characterizing cyanophages isolated from the Copco Reservoir and coastal lakes in Oregon in order to understand how, if at all, cyanophages induce or restrict toxic cyanobacterial blooms.