Exploding Estimates of Genetic Diversity in the Sea

There has been a paradigm shift in our understanding of the oceans. In contrast to the common perception that most life in the oceans is visible to the eye, more than 95% of marine life, by weight, is microbial. These microbes produce about half the oxygen on Earth, and drive carbon and nutrient cycles on a global scale. On average, these microbial communities include about a million bacteria and 10 million viruses in each mL of seawater. In fact, viruses are by far the most abundant life-forms in the ocean, and if stretched end to end would span about 10 million light years, or further than the nearest 40 galaxies. This universe of viruses is thought to kill about 20% of the living material in the ocean each day; consequently, viruses are of great environmental significance. It is also remarkable is that marine viruses harbor perhaps the greatest reservoir of largely unexplored genetic and biological diversity on Earth. Metagenomic studies of environmental samples have revealed extremely high levels of genetic richness of both DNA and RNA viruses, with most putative coding sequences having no obvious relatives in databases. Viruses have evolved to be fine-tuned “machines” that are strictly dependent on the host organisms they infect for replication; hence, the proteins encoded by viruses interact strongly with their host organisms, and are likely a source of many unknown proteins with a wide range of functions. Marine microbes recovered in coastal waters will likely fall under the control of national jurisdiction, but what about the vast majority of microbial diversity that lies in international waters? Should the commercial potential of these microbial resources belong only to the discoverer or should this potential be distributed amongst all nations?