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The United States ranked fifth globally in chondrichthyan catch in 2011, pulling in more sharks and rays than South Korea, Japan and Thailand combined.

Classifying these fish correctly makes the United States the third-largest chondrichthyan exporter by volume and the second-largest by value.

The chondrichthyan immune system shares many features of the innate and adaptive immune systems of mammals.

A detailed whole-genome evaluation of a chondrichthyan and comparative analysis with the available genome information on osteichthyans and a jawless vertebrate might help us to understand features unique to chondrichthyans and provide insights into the ancestral state of gnathostome-specific morphological features and physiological systems.

Overall, the genome is the least derived among known vertebrates and is therefore a good model for inferring the state of the ancestral chondrichthyan and gnathostome genomes.