Rice is the first crop plant to be fully sequenced because of its indispensable importance as a major staple food for about a half of the world population, which is expected to be 1.5-fold of the current number after 50 years. And the rice plant also serves as a reference genome for all cereal crops, such as wheat and corn.

This paper provides a comprehensive synthesis of information about the rice genome, summarizing the results of the sequencing, assembly, and annotation work accomplished by an international team of researchers (the International Rice Genome Sequencing Project, IRGSP).

Enlarge “This paper provides a comprehensive synthesis of information about the rice genome, summarizing the results of the sequencing, assembly, and annotation work accomplished by an international team of researchers (the International Rice Genome Sequencing Project, IRGSP).”

The project also serves as a model of international collaboration which includes many countries in Asia, Europe, North and South America, and the public availability of data. This kind of collaborative project is more difficult to accomplish when the focus is on a species of economic importance than when it is on a model species that has no direct economic value.

In the case of rice, whereas rice production is vital to the economies of many countries and also to the profits of several private companies, there are competing scientific, economic, and intellectual property rights issues that make it difficult to complete an international sequencing effort.

Yes, it describes a new synthesis of knowledge and provides links to all the underlying data that was generated over the course of the sequencing effort. This data serves to understand the rice plant by its fundamental information on inheritance and further helps coordinate and facilitate the sequencing of other plant genomes, particularly other grass and monocot species.

Knowledge of the sequence of specific genes will enable researchers to tap into the natural genetic variation in a wide collection of rice germplasm, particularly from the wild rice species. Together with the sequence of the Arabidopsis genome, another plant genome that has been completely sequenced, the rice genome also provides fundamental information on the diversity of gene and protein sequences that divides the monocotelydonous and dicotyledonous species in the plant kingdom.

The paper provides a synthesis of information about the rice genome, including the extent of sequence coverage, with 99.99% accuracy, along with the amount of euchromatin and heterochromatin, as well as the number, identity, and distribution of gene models, their size and structure, the relative abundance of putative orthologs within different functional categories compared with other plants and non-plant species, as well as the types, distribution, and relative abundance of transposable elements, microsatellites, and other types of repeats, along with evidence for horizontal gene transfer between the nucleus and the organelles and the evidence for extensive synteny with other cereal species.

Together, this information makes it possible to link research aimed at addressing questions of basic biological importance with applications in agriculture and plant improvement aimed at improving the productivity and sustainability of the world's major food crops.

Since 1991, Japan has been pursuing large-scale analysis of rice through the Rice Genome Research Program (RGP). Upon completion of the first phase of the program in 1997, we established the blueprint for a second phase that included the sequencing of the entire genome. At the same time, research groups from other countries also showed enthusiasm for rice genome sequencing.

So a workshop was held at the International Plant Molecular Biology Conference in Singapore in September 1997 to discuss the feasibility of an international format to sequence the rice genome. It was unanimously agreed that the community would benefit more by forming an international collaboration to facilitate sharing of resources and to accelerate the completion of sequencing.

Researchers involved in this project came together from different communities and countries to accomplish the goal of generating a complete genome sequence of rice and ensuring that it was publicly available. The major groups included experts in genome sequencing, experts in rice biology and genetics, and representatives from the funding agencies of many countries.

The major obstacles included attracting and maintaining funding over the course of the project, staying efficient and keeping an accelerated pace, continuously upgrading sequencing technologies to take advantage of new developments, providing an inclusive environment so that international groups could contribute to the sequencing effort, and keeping all groups coordinated and in communication with each other.

Yes, there are social, political, and economic implications because rice is such an important crop worldwide. Many countries, including Japan, China, India, and Thailand have major rice research programs that are leveraging the rice genome sequence to improve the competitiveness and productivity of rice production in their respective countries.

Other countries, including the US and EU, are using the rice genome sequence to facilitate the sequencing and analysis of the maize, sorghum, barley, and wheat genomes. There is tremendous momentum around the world to build on the availability of rice genome sequencing to identify genes of agricultural importance and to develop new crop varieties that will improve the productivity and sustainability of crop production systems in the future.