Assessing Symbiodinium diversity in scleractinian corals via pyrosequencing-based genotyping of the ITS2 rDNA region

The persistence of coral reef ecosystems relies on the symbiotic relationship between scleractinian corals and intracellular, photosynthetic dinoflagellates in the genus Symbiodinium. Genetic evidence indicates that these symbionts are biologically diverse and exhibit discrete patterns of environmental and host distribution. This makes the assessment of Symbiodinium diversity critical to understanding the symbiosis ecology of corals. Here we applied pyrosequencing to the elucidation of Symbiodinium diversity via analysis of the Internal Transcribed Spacer 2 (ITS2) region, a multicopy genetic marker commonly used to analyze Symbiodinium diversity.