The new "finished" sequence and analysis of rice Chromosome 10, published in the June 6 issue of Science, confirms that the rice genome is closely similar to that of other grains, particular sorghum and maize. The study also offers a close look at the compacted short arm of the chromosome, which is a gene-poor heterochromatic region of the rice genome.
Robin Buell, who leads the rice genome sequencing team at The Institute for Genomic Research (TIGR), says the "finished" sequence which helped researchers identify about 1,700 additional rice genes shows the importance of completing a draft DNA sequence. "This work clearly demonstrates the importance of finished sequence," says Buell. "The finished Chromosome 10 sequence of rice will be a major component for future comparative studies of other cereals, such as corn and wheat."
Chromosome 10 was sequenced by a U.S. group led by Buell at TIGR and by Rod A. Wing at the University of Arizona with funding from the U.S. Department of Agriculture, the National Science Foundation (NSF) and the Department of Energy. That effort was part of the International Rice Genome Sequencing Project (IRGSP), a public effort that is completing the sequences of all 12 rice chromosomes, which have a total of 430 million DNA base pairs.
Rice is one of the world's most important foods, providing more than half of the daily calories for about a third of the world's population. The IRGSP sequenced the genome of the japonica subspecies of rice (Oryza sativa) that is cultivated in Japan, Korea and the United States. Another rice subspecies, indica, has been sequenced by a Chinese institute.
The IGRSP public consortium announced in December 2002 that it had completed an advanced, high-quality draft genome sequence of rice. The data freely available on the internet to a
Contact: Robert Koenig
The Institute for Genomic Research